SE under the hood mods????????

I have a stock '02 grand prix SE, i cant find any damn mods for it! (except appearance of course) i was about to put some american thunders on it, but they told me the last SE they put those on messed up the computer system, damnit I want the most out of my engine! lol what can I do no matter how large or small.....

Plans for the future when I have the $$$$:
Drop in an LS1 or LS2 ( I know, easier than it sounds....)

http://www.rsmracing.com/catalog.htm
http://www.milzymotorsports.com/
just look under 3100

damn thanx man, i couldnt find anything.........