trans am stock car?

ok so i went to my first stock car races the other day and i fell in love lol. so i started to look into tryin to race and i rembered that i have a 1978 trans am and i was wondering whitch form of racing was the cheapest to start in with my trans am. ALSO what all would i need to do to my car.

money isnt a BIG deal i just want to do it the cheap way cause i dont want to poor alot of money into my car to potentialy crash it because i have never raced befor, so please help guys  

You'll probably go into a Pure (Street) stock class which keeps everything stock on the car i.e.  motor, tranny, suspension, rearend.  
Getting the car race ready isn't a hard thing to do.  You would remove all glass, chrome, headlights, tail lights, any flammable material,  pretty much gut the car out. Then you need to put in a roll cage which can be bought for around $400. Then a racing seat and belts. Most tracks require the gas tank be taken out and replaced with a fuel cell.
There's also alot of little stuff to do but that's the basics of getting a car race ready,  You're best bet is to figure out which track(s) you're goin to race at and get a set of rules which will give you good idea of what all you need to do.
Once you get out to the track, at most tracks,  the other drivers in the class will help you out with things about setting up your car, little things to do here and there.
Hope that helps you some.  It's always good to get new blood into racing.