I don't think a referral to a shop is verboten on ClubB5. Check the local boards on the forum pages and look for some fellow drivers in your area. As well, try the regional forums on vwvortex.com... you can probably learn a great deal about a shop by just reading the testimonials, good or bad. It often pays to drop in for a visit just to introduce yourself and see what the staff are like. NGP out here is great to work with while other tuners have a long way to go in the earning the business department.
Inter Auto on Convoy, 1blk south of the 52 Fwy carry OE parts.
You can check parts4vws.com in Temecula, and purems.com in Temecula.
Howbar motorsport in SD, Group 5 in SD.
Probably a couple others I'm missing..