I think my compressor bit the dust,,,car has 180k,,,dont want to put the money into a new compressor,,,,how expensive or can it be done to just use regular shocks ???

HERE IS THE ANSWER TO YOUR QUESTION
MONROE 90007

so do you leave exsisting coil spring on the car ??? Just remove air shocks and replace with these ??

Just leave the coil springs on the car and yes replace with these.
OR
you can get a universal air shock line kit and just air them up that way.
I think some have done it here you might look in the Pontiac Bonneville section