Hubes,
Your A/C compressor should be a Nippondenso 10P15F. There should be a label on the back of the compressor with this information on it. Next, your A/C clutch coil is an electromagnet. You can test it by disconnecting it from the cars system and applying battery voltage to it. I should become a strong magnet. If it does not become a magnet, it should be replaced. There are other tests you can do that you can find in the local library reference section in Chiltons, Motors, and/or Mitchels auto repair manuals. The tests can be done with a simple volt/ohms/amp meter. The clutch coil, pulley(with bearing), and front clutch face come as a set. The price will vary depending on where you buy it, and whether or not you get any discount. If you buy an OEM unit from a Ford dealer's parts department it will be about $180. If you get it from an aftermarket parts store, e.g. NAPA, it may be $30 to $50 cheaper. One posting indicated that Auto Zone sells a set for about $90.
If your A/C system does not have any refrigerant charge, due to leaks, then remove the compressor. The compressor should take 7 pounds of torque, or less, to turn without the manifolds attached to it. An inch pound torque wrench is better for small amounts of torque. (7 foot lbs = 84 inch pounds) Turn the compressor with a torque wrench set at 7 lbs clockwise. I start with 5 pounds and work my way up. If it takes more than 7 lbs to turn the compressor, then replace the compressor. Again, spend some time in the local library, or borrow a service manual for your model and year car. Your local Ford dealer may even let you borrow their shop manual so you can copy the pages you need to diagnose and fix your problem. A new compressor from Ford is about $300. A rebuilt compressor is about $230. If you replace the compressor, replace the filter dryer also. Lastly, if you open up the system them consider converting to R-134a. R-12 is about $60 to $70 a pound. R-134a is less than $10 a pound, and is just as efficient at cooling. Hope this helps, if you need more e-mail me. rangerj