I agree with the above posters, I wouldn't go and invest in a complete track setup right away. The autox will help you to improve your skills and learn how to drive the car then i would start modding it as you go.
After that I would suggest doing some drivers schools at tracks and get some instruction. Both of these are pretty good alternatives to all out racing. If that doesn't meet your need for speed build a spec e30.
If you want to race wheel to wheel its going to cost $$ and probably more then your job will provide.