http://www.vortechsuperchargers.com/product.php?p=102
this is the chevrolet website for the parts. hope it helps

http://ls1tech.com/forums/

You want a supercharger. GMs don’t take well to turbos. I have a m62 in my car and it’s a decent supercharger. There are tradeoffs between centrifugal and roots superchargers mainly in the setup. Either way it’s going to require some work not only with the parts (s/c, intake manifold, heat exchanger, injectors, etc.) but you’re going to need to have it tuned as well. You’ll get less power than with a mid-sized turbo but a supercharger will feel more like a corvette (instant power).

This guy’s pretty good with roots superchargers: http://www.stiegemeier.com/home.html