UT,
I just went out and looked at the car, which happens to be here today.
I bought everything from:
www.rpmoutlet.com
Diablo switchable chip, Mac bolt-on cat-back dual exhausts and cold air intake. There is also a phone number on their site, and you can talk to one of their tech reps.
All you'll need is to pull the pass. footwell cover and read the code marked on the outside of the ECU case, so they can flash the chip for the right program for your car.
They claim 18HP for the chip alone in the 3.8 V-6, and I probably got another 40 or so with the cold air intake and exhaust system, for under $1K, not bad.