I know what you're thinking but hear me out. Plenty of reasons for doing an online background check exist, and not all of them are sketchy.
In fact, everyone should do at least one online background check on, you guessed it, themselves. After all, if you can find out sensitive information about yourself with a little (free) online sleuthing, there's no telling what employers, stalkers, and ex-girlfriends or -boyfriends will be able to uncover.
So here's how to do a thorough online background check without dropping any cash.
If you know your target's name
If you know name of the person you're looking for, the first places you should check are the usual venues, good old search engines and social networks. Google, Facebook, LinkedIn, and Twitter are all good stepping-stones for discovering valuable information about people.
Remember to use advanced search techniques when looking people up on Google or other search engines. Just enclosing your search terms in quotation marks will help immensely in weeding out non-correlated or irrelevant search results. If the person you're searching for has a common name, you should also add any information you know about them after the quotation marks. For example, if I search for "sarah jacobsson purewal" pcworld, I'm going to get more details about the Sarah Jacobsson Purewal who writes for PCWorld, helping to narrow my search down a bit.
Use any information you know about this person, including places of work, types of work, schools they've attended, cities they've lived in, and the names of other people they know. You can also use site-specific searches if you're looking for someone within a school or business. For example: site:pcworld.com "sarah jacobsson purewal" will give a list of search results found only in the PCWorld.com domain.
Searching your social networks
Social networks are fantastic sources of information and it's all completely self-volunteered. This is why social networks are particularly handy for employers because if it's on your Facebook page, it's not only information about you, it's information you've chosen to share with the world.
Facebook is indisputably the social networking standby, no surprise, as it boasts 500 million users. You can search for people by name and e-mail address, and modify the results by location, school, and workplace. If nothing shows up, they may have made their profile private and unsearchable.
If that's the case, you can do a site-specific Google search, and any public pages or groups they may have commented on will show up. For example, my personal Facebook profile is private and will not show up in Facebook search results, but if you type site:Facebook.com "Sarah Purewal" into Google, you'll see that I have commented on PCWorld's Facebook page. You can now see my profile picture, as Facebook doesn't allow users to make this private, even if you still can't search for me using Facebook's search.
Alternatively, you can use Openbook.org to search across Facebook's public pages (including status updates) for any search string you want and find search results listed with names, profile links, and pictures, perfect for your background check.
Other social networking sites, such as LinkedIn and Twitter, are also worth a look. LinkedIn usually reveals much less information about a user, because it's primarily a work-oriented social network. However, it is an excellent place to verify user's résumés and work histories (though, of course, a user can lie on his or her LinkedIn profile very easily).
Twitter is a different type of social network. Unlike Facebook and LinkedIn, Twitter asks for very little identifying information from their users. Thus, you'll often find people's Twitter accounts via their Facebook or LinkedIn pages, not necessarily by searching Twitter. Twitter can still give you a wealth of information, though it's more likely to give you an insight into their personality, interests, and style, rather than information you can use to find their address or phone number.
Find the basics: Phone number and address
Okay, so you've Googled your target and discovered all of their sordid beer-bong photos on Facebook, but what you really want is to be able to contact them. How can you get their phone number and address?
ZabaSearch is a fairly accurate phone number lookup service. It offers a free way to look up people's phone numbers (you can narrow it down by state), along with premium services for reverse phone number and social security number lookups. I say "fairly accurate" because while ZabaSearch's database includes listed and unlisted numbers, it's hit-or-miss when it comes to cell phone numbers and who doesn't have a cell phone these days?
WhitePages.com also offers a free phone number lookup, and throws in an address to boot. WhitePages appears to update its database more frequently, as it found a recent address change of mine that ZabaSearch missed (within the last year). However, it does not list unlisted numbers. WhitePages also offers a premium, reverse phone number lookup, and will show you the location of the phone. Of course, this is simply the location of the phone's origin, and is based on the phone's area code, when I look up my phone number, for example, it says my phone is likely located in Conway, South Carolina. (This is incorrect, as my phone is currently located in California, but my phone's area code is from South Carolina.)
Criminal and public records
Finding an address or phone number is child's play. Only when you're looking for criminal and public records do things start to get interesting. If you want to know if your hot coworker has ever been divorced, or if your neighbor might be running a drug ring out of her apartment, this is how you can find out.
CriminalSearches allows you to do a criminal history check on people by name. You can also narrow down the search by city and state, though these are not required fields. The search results include the offender's birth date, address, and what types of criminal offenses they have committed (behavioral, business, drug/alcohol, sex-related, theft/robbery, violent, or traffic/other). It does cost money to see the details, and you should remember that some states include minor traffic citations as offenses, so they may not really be "criminals," per se.
If you're looking for other types of public records, such as marriage records, birth records, or death records, SearchSystems offers access to free public records sites. You can search by type of record, zip code, state, county and state, or city and state, or you can search international records by region. Instead of "searching," however, you will end up being directed to the Website that contains the records you're looking for, whether it's Clinton County Cemeteries or California marriage licenses before 1900.
VirtualGumshoe also has a database of public records Websites, including wanted lists, marriage and divorce records, voter records, and death records. Some of these sites are free, while others are pay services, but little icons by each listing will let you know which is which.
If you don't know your target's name
Let's assume you want to search for someone whose name you don't know. Say you got a random phone call at 4 a.m., or someone has been spamming you with a certain e-mail and IP address combination, or you really want to find out who that jerk is on the forums you frequent, who goes by a particularly unusual handle.
Phone number/e-mail address
Most services that offer phone number lookups also offer a reverse phone number lookup, in which you input a phone number to get information about the person calling you, for a nominal fee (usually around $5). However, this information can be inaccurate, as I pointed out above, an initial reverse phone number lookup on my phone places me in South Carolina.
One of the best places to do a reverse phone number lookup--and a reverse e-mail lookup, while we're at it, is Facebook. While you can't look people up by phone numbers (even if they have it listed on their profile), you would be surprised at how many people leave their numbers on their friends' public walls. If you search for a phone number on Facebook and it's been left on someone's wall (or on one of those "I lost my phone, need numbers" group walls), it will show up in the search results.
As for e-mail, well, you can search for people on Facebook by e-mail address. And even if their e-mail address isn't publicly available on their profile, if it's in any way affiliated with their profile it will show up.
Also remember to plug phone numbers and especially e-mail addresses into Google, as people tend to slap their e-mails publicly around the Net without even thinking about it.
If you know nothing about the person you're trying to look up except for their username or online handle, fear not. So long as the username/handle is reasonably unusual, you'll be able to find a decent amount of information (which you can then use to perform other searches).
Pipl is an aggregator that searches the "deep web," or parts of the Internet that are often missed by regular search engines such as Google. Pipl allows you to search by name, e-mail address, username, or phone number. Pipl then crawls the Web and aggregates all search results that contain your terms, so it's more of a one-stop shop for results.
Pipl is excellent for hunting down information about people whose name you do not know (as for people whose name you do know, it mostly just finds what you can find on Google and social networks). The username search is particularly useful, especially because a lot of people use one handle across the Web.
Other aggregator sites also exist, such as ZoomInfo, which aggregates job and company information; iSearch; and Wink. Unfortunately, aggregator sites can be as much of a pain as they are a convenience, as they often confuse people and spit back a mix of related and unrelated results.
Web domain/IP address
If you want to find out who owns a domain, the process is pretty simple. The Whois database keeps a record of all domain registration data, and you can search it via a number of sites. Whois.net and Whois Source are just two sites that allow you to look up the registration data for any domain, and, if you're lucky, figure out who the owner is. Users are required to provide an address and a phone number when they register a domain. Of course, many Website owners opt for private registration, which hides their personal information.
You can also look people up by IP address on Whois. You can use tools such as Geo IP Tool to search the Whois database and find out some info on the IP, specifically where the person is coming from. For example, my current IP is 188.8.131.52. If I enter this information into Geo IP Tool, I can see that I'm located in New York, New York, zip code 10019. Sure, that's not enough to be able to find out my phone number, but it's a start.
While Web domain and IP address lookups may seem like a dead end, they're often just the start of your search. If you can gather any information from the Whois database, you can use what little you know to aid you in your further searching. For example, if you're looking for me and you find out that I'm located in New York, thanks to my IP address, you can probably disregard the search results that put me in other places.
Well, there you have it, folks. Go forth and stalk yourself without spending a bundle. Have your own people-finding tips? Leave them in the comments!