If you are trying to track down information about a person using only their cell phone number, then Find Name By Phone Number can help you find the reverse cell and phone numbers.
If you are trying to track down information about a person using only their cell phone number, then Reverse Business Phone Lookup can help you find the reverse cell and phone numbers.
If you have in your possession a residential phone number but no idea that the number belongs to or what address it relates to you can use Phone Number Reverse Lookups..
Reverse Lookup By Phone Number contains a database of hundreds of millions of cell and unlisted phone numbers, complete with information about the owner.