Sure you can find out the information. Any dealer can get that information for you, for any phone service, given you provide some cash in the process ...we do work on commision you know. Anyways, there's a much simpler way though...reverse lookup on the phone number. For starters, how do you know its nextel. Also....why can't you just change your phone number and stop worrying about it...instead of you becoming the bad guy and possibly ending up in jail?