If you are looking to be competitive in the STR autocross class, here's a very good package of wheels and tires. Take a look at the TRMotorsport C3 and the Bridgestone Potenza RE11.
In 17x9, the wheel works on all four corners and only weighs 19.2 lbs. They are available in three different finishes depending on the look you want.
The Bridgestone tire is as good as it gets for a street tire. In fact, they are almost a track tire for the street. With this package and a little added negative camber, the car will be very quick in the autocross.
So if you want to be the top dog in your area, start here.