New Guy Here
For Power:
First read all stickies on LS1Tech.com -then:
Lid
Catback (or true duals if you wish)
LT headers / ORY (or true duals if you wish)
Port throttle body
LS6 intake
Tune
NOS
cam
Heads
Forced Induction
Other non-power (but still great) mods:
Shifter
Gears
Suspension
Wheels
Tires
Rear end
Clutch
Just a few ideas for you to think about. It really comes down to what you want to accomplish and how much money do you want to spend to do it. The search function works well on this site as most (if not all) of these topics have already been addressed in the past. Good luck!

