Go to this faa website

http://www.faa.gov/licenses_certific...irmen_inquiry/

Go all the way down to the bottom to start search. You'll have to type in some info about yourself, but once you fill out all the info it should narrow your search info down to a few names. Then you can find the registered mailing address for that cfi.

* After I posted this I realized FlyerJosh had already posted the same thing. Sorry.