1993 Sunbird A/C Not Working

I was just wondering, where is a good place to start troubleshooting on A/C not working???

Blower motor works fine, heater works fine, just no A/C!

First, check refrigerant pressure with the proper type of kit -- your car should be an R-12 system unless it has been converted to R-134a.... If the pressure is good, check the refrigerant pressure cutout switch in the line by disconnecting the harness and jumping out the wires. This switch cuts electrical current to the compressor clutch if pressure drops too low, and sometimes they can go bad and keep it from running even if the pressure is fine, because they tell the computer it is not.