Transmission for a '92 firebird...?

Anybody know where I can find a good, affordable racing or sports transmission(automatic) for my firebird?

You can turn your tranny into a more performance based type tranny with the use of a shift kit and some new performance Servo's and high stall torque converter but www.summitracing.com (http://www.summitracing.com/) also sells racing tranny's if you decide to just replace it.
John