If an unknown number is causing you a bit of grief, your first thought might be to find out who is on the other end of the line. Have you ever been frustrated by attempts to look somebody up in the white pages or via directory assistance?
This is the process of locating or discovering the owner of a mysterious phone number. Cell phone numbers, however, are not easily obtainable and the directories that are produced for all the cell phone numbers that exist are huge, time consuming to assemble and costly to produce. Using reverse cell phone directory you can find information on any cell number in North America.
But, if you aren't able to find the person's information for free, you are pretty much out of luck. Most of the services charge you one time fees. There are quite a few, so try more than one when it seems the information is simply not out there.
To summarize, if you want to trace cell phone numbers free directories are not going to help you. For more information on reverse phone number searches, check around this site.