J & P Cycles, Inc., Anamosa, IA -  I bought a lot of parts from these guys and it was always good.

http://www.jpcycles.com

West Coast Choppers it's fun to look at.........   parts prices aren't really bad either!

http://www.westcoastchoppers.com/

This is a great site for Sportster people.  You can see a lot of nice bikes and post your own pics!

http://xlforum.net/index.html