You can usually make these for less then $10. They are usually a 3 position switch a 2 different resistors. 10ohm and 20ohm. All they do is connect to usually the blue wire on the transmission and makes the torque management I believe its call become lower or off completely. I made these for a few people for their s10s and camaros.
http://www.yourcobalt.com/forums/performance/30340-10-b-m-shiftplus-diy.html
s10 forum use to have a good how to if you can find it.
On the inside my car looks like a fighter jet.