A budget would help. You're going to want a transmission though. To get to 12's your be breaking them like no one's business.
Triple Edge Performance - Home Page for the Trans.
A turbo kit would get you there for sure.
ZZPerformance - Go Fast... Not Broke | 3800 | Ecotec | Sonic/Cruze
Alot of LS parts will work on your car. It's just a little bit harder to make them work being a transverse motor and all.
I don't know alot about the LS4's but I think someone even makes headers for them now.