I don't know about turbo's for the 2.4 because I have the 3400, but I think you can find one. A good place to start for some power is CAI, exhaust, and headers.
The razzi kit is the only ground effect kit right now. You can find it on
www.razzi.com or www.pfyc.com(banner at the top of the screen). But there are a few body kits out, check
www.andysautosport.com and click on body kits then oldsmobile, there is another body kit I can't mention but email me and I will tell you, and an OSV kit is in the works. I may have forgot one but I don't remember right now.
Best place to look for the 2.4 is in the 2.4 section, read through all of the info in there and you'll find all the answers you need.