Before mods happen, you need to make sure your engine is as tuned as it can possibly be.
This means new filters (fuel and air, if they haven't been done in a while), new plugs and wires, O2 sensors, maybe a top-end engine cleaner.
You will also need a scanner, preferably one that shows realtime data, and shows things like KR (this goes back to that other question you asked). If you get KR, you need to find the root of the problem BEFORE modding...otherwise you will make it worse afterwards.
A cold-air intake would be the first thing on the list....it usually is.
Welcome, downwardly mobile yuppies, to the dawn of the Age of Nefarious.
1993 SSEi - FrankenJinx - dead and gone.
1994 SSE (136K strong) - 180* t-stat,HD alternator, most unequipped SSE on the club, XM radio, Kenwood CD/MP3.
2006 Chevy Malibu Maxx LTZ - Custom 2.25" manifold-back exhaust w/FM-80. Probably the only Maxx with this system.