1. I own a 2.2 LS, so im wondering if anyone has installed tweeters and where the best place to put them is

and

2. Aside from speakers, Head unit, subs, and amp, what extra equipment will I need (Im having a friend of a friend install it for cheap)

 

Power wire
Ground wire
Remote wire
Speaker wire
RCA cables (1 to 3 sets depending on how many amps your running)
Radio wire Harness
Dash Kit (Trim around the radio)
Antenna Adapter
Inline Fuse
Ring Terminals
Soder, heatshrink,electrical tape
PATIENCE, and lots of it!

The stock tweeters come in the sail panels (right on the opposite side of your side view mirrors) they seem to work well there