Jotech has done a Greddy TT install. They seem to be the biggest here in town, but not necessarily the best. I've never used them for anything, and have heard mixed reviews.
I always use Sam at Crossover Auto. Havn't done a turbo upgrade but had him do an engine swap on my mazda a few years ago. I know right now he has a TT g37 getting a custom widebody made. They fabricated the new panels out of sheet metal and welded them on over where the previous shop had cut the stock fenders. Body work looks great, way better than the nasty widebody kit that was on previously.
You can check out some of his customer cars on the FB page:
Sam CrossoverAuto | Facebook