You can try these:
goantiques.com AOL classifieds ebay celebritysigning.com If you meant where you can send fan mail, here are some addresses I've heard of. I'm not sure which are current, except probably the DH one.
Desperate Housewives
Touchstone Television
100 Universal City Plaza
Bldg. 2128, Suite G
Universal City, CA 91608
Teri Hatcher
Brad Cafarelli, Publicist
Bragman/Nyman/Cafarelli
9171 Wilshire Blvd.
Suite 300
Beverly Hills CA 90210
310/274-7800
Teri Hatcher
Eli Selden, Manager
The Firm/AMG
9465 Wilshire Blvd.
Beverly Hills CA 90212
310/860-8000
Teri Hatcher
Writers & Artists Agency
8383 Wilshire Blvd.
Suite 550
Los Angeles CA 90211
323/866-0900
Teri Hatcher
C/O William Morris Agency
151 El Camino Drive
Beverly Hills, CA 90212