I found a handy little service called the Reverse Phone Detective, its really handy for checking up on annoying or unknown calls.
Do you ever get those phone calls that come at the most inopportune time? It never fails; Ill sit down to dinner with the family, and the phone will start ringing. We never answer the phone during dinner, but after dinner I like to check up on any calls and see from whom it came. On most nights, there are zero messages, no matter how many phone calls.
Go try the reverse phone number finder and see what kind of information you can find.