Do a search on audiworld.com in the 12V forum for these things:

Abnormally Aspirated
throttle body
Stage 3 MAF
Stage 3 Velocity stack
Snub mount

There is a guy on that forum who makes performace products for the 12V engine. His name is Mance, and goes by the screenname of "1PissedOff90".

 

I just got my water pump, and timing belt and all the pulleys replaced, including belts. The dealership wanted at least $1800, but I found a shop that works on german's all the time and has a great reputation, www.thespeedshop.net, and charged me only $900 and I am very satisfied with there work. If your ever in the upper IL or lower WI area, and need work there you go. They also worked around my schedule, which I picked it up Xmas eve.