depends on what you want.
I'd say watch the classifieds on this site. I've gotten lots of stuff for good prices there. My grill, my headlights, my springs, a short shift kit, kamei air ducts, audi pedals, the list goes on.
If you have a specific part that you want, post on here. I know of a few different dealers who will hook up awesom eprices, just depends on brands.