I don't drift my supra, but I've done it in other cars.
You probably want to do this cheap mod first. If you really get into the sport, then spend $$$$$$$ on suspension mods.
http://www.supras.com/06/techcenter/display.php?QID=44
You could also just put a jumper wire in the Ts and E1 connectors holes. This will make the sport position into the firm condition, and normal into sport.