How does one get into racing? That's like asking, how does on begin writing the next great American novel? Or, how do you evolve into a state of higher consciousness through meditation? You just start doing it. The best way to become a competent race car driver is to race. Don't do it on the street though; go to your nearest track, pay the fee, listen to instruction, and drive.
It's pretty much public knowledge at this point that the Donut crew has the best gig possible, and this video on track preparation proves that. I mean, what other job is going to pay you to race your "borrowed" drop-top 911 around a track all day?
So take in the tips from the pros, and then, when next weekend rolls around, head to your local race track, fire up your stock Forester and go racing!