You can search Facebook, Google, or photo search engines, for example, to locate someone who sent you an e-mail. It’s hit or miss, to be sure, but you can sometimes score a direct hit.
Conducting a reverse phone search is theoretically a lot more straightforward –one enters a telephone number in a Site and discover the person’s name and address.
Unfortunately, online reverse cell phone lookups remains one of the few types of online searches it’s extremely difficult to obtain free of charge. There are only a few, and just what works today for me personally may well not do the job in the future.
That said, the best way to look up someone based on a phone number right now is Facebook. That shouldn’t surprise anyone based on the service’s spotty privacy record, but in this case it certainly works to your advantage if you’re looking up a phone number. Just open Facebook and enter a phone number in the search box at the top of the screen, then press Enter. If that individual has associated their phone number with their Facebook profile, they will appear as the top search result, regardless of their privacy settings and even if you are not friends.
Of course Google is as well very useful in looking up phone numbers and find out who is calling you, when in doubt Google It!