IF you go to Yellowpages.com or Yellowbook.com you can do a reverse look up on the phone number.   If it does not come up under businesses - change to People.  At the very least you can get some info for free -

Intelius (via these directories) also provides details on unlisted numbers for a fee..

receving calls from this number - want them stopped, costing hundreds of dollars and cell phone company will not credit them off or help stop them!!!

son has been receiving calls from this number and it is causing us a huge cell bill - cannot find out who it belongs to - needs to stop!