Y'all crack me up . Those are some good gag parts for sure . Not all autozone guys are that green though . some do know how to play along with the jokes too .  

just go to nopi.com and browse through what they've got to offer for your car.
New tires are always the best way to start off with when modifying your car. You can get a new spring/strut assembly to help the handling some more. A cat-back exhaust and air filter will help your engine breathe more effectively.
Just some minor mods to start off with, then once you get the snowball rolling, you'll add a turbo and adjustable coil-overs with a set of 18" rims and so on...  

I was just reading through an old issue of SCC when I came across a column of Daves. An abstract of his masters in geektitude.

"Getting good tires is teh second most effective thing you can do to improve handling.

Learning to drive is the first"  

im not sure, but isnt the four cylinder from the 02-06 camry the same as the one in the scion tc? i dunno how different it is from the engine in the 97-01 camry though.