Thermostat starts, air starts to blw, sometimes the pilot doesn't light. I turn off the thermostat wait turn it back on and it will light..?

We need a much clearer description of the type of system and the problem.

You mentioned that the PILOT light doesn't light? I believe that the pilot light is lit all the time on a standing pilot system. Or is this a hot surface or intermittent spark ignition system. Do you mean the burner doesn't light?

I could thing of several different reasons for those symptoms, but until I know more of what the problem actually is I can't be of much more help than to say "call a professional repairman".