Does your AC Compressor ALWAYS spin

Sorry to bust in on this thread, but it reminded me of my AC problem. My AC doesn't work. When I have it running, the clutch doesn't seem to engage and the compressor doesn't spin when the AC is turned on. Everything else seems to be fine, the only other thing I could think of is the system needs to be charged, but I have no idea of how to check that.

What could be the problem and are there any do it yourself fixes, or is this a job for a shop?

if the belt goes around it, it better spin all the time.