Well, you have a few options.
Call the local police. -- If this is
REALLY as important as you make it out to be, then call the police.
www.ussearch.com -- There is a fee involved, but the will be able to tell you what you need to know; if it's that important that a few bucks aren't going to matter, eh?
The phone book. -- 'nuff said
Really, you're not going to find much on the net that will tell you if said person is still living in the area or not. You are going to be relying on phone records; if said person does not have a phone in their name then you're S.O.L. I'd assume that said person is not the kind of person who would write a BIO about themselves on a webpage with an address and telephone number.
-SF