TP2Location: Track down where that wrong number came from
TP2Location can help. Well, to a degree. It won't give you a street address, but if you type any phone number into this web tool you'll get geographic information describing where the call came from. While this may not help you track down the person keeping you awake at night, it might help you decide whether you should place that overseas business call now or wait a few hours until the sun has risen on the other side of the ocean.
TP2Location also has a semi-useful Google Maps feature, which will bring up a map of the country corresponding to the phone number. While this would be great if you were looking at a country the size of Vatican City, the results for New Jersey and California phone numbers are identical: A map of the entire US.