Does the a/c switch light up when engaged? Did it when the a/c was working properly? I would change the fuse anyway just to make sure that that's not the problem. Have you checked the power and ground wires from the compressor itself. The power side has a connection between the (on my 92) black wire coming out of the compressor and the green wire that powers it. Check to see if that may have come apart. Also check that the black ground wire is properly connected. I'm far from an expert but I have just been doing some work on my kid's 92 and am familiar with the a/c wiring. If the switch on the dash lights up I would think that the circuit is being completed and perhaps the a/c compressor is the problem. If not then maybe the power is never getting to the a/c compressor in the first place. Good luck.
Eric