We used Craig's List (www.craigslist.org). Took about a week to actually get the money order and hand the keys over. But it was a good experience -- for me, using email for the first contact is a good thing! And with Craig's List, the buyer can't actually see what your real email address is.
Momma to 8 y.o. DS and 5 y.o. DD. Married to a Maker!