I buy domains at SnapNames and Sometime at Godaddy aftermarket but those are mostly expired ones.
SnapNames auctions + tons of DATA
http://www.freshsnap.com
traffic domain handregs / expired guide:
http://www.webmasterinter.net/2009/1...ecent-traffic/
This might also help ;)
http://www.webmasterinter.net/2008/0...ce-comparison/