A/C not turning on

I have a 97 GTP with 205,000 miles on it. The A/C was working over the weekend, but when I turned it on today, it didn't work. Here are some of the observations I made:

1. The light next to the A/C switch comes on.
2. I don't hear compressor clutch engaging.
3. I believe that if you turn the A/C on while the car is parked, the fans come on immediately. I drove back from work so car was at running temperature and when I turned the A/C on, the fans didn't come on.
4. I checked the two fuses marked HVAC on the fuse panel and they seemed ok.
5. A new compressor was installed last year.

Any help in tracing me the problem would be appreciated.

Your next step would be checking refrigerant pressures with a guage set. It sounds as if you may have sprung a leak and are now low/out of R134a.