Here's one you can try:
http://forums.pelicanparts.com/showthread.php?threadid=270086
I didn't use a compressor, but prefer a regular pump as I would use on bike tires. The feel of the applied pressure is much better. The only problem is attaching the line to the brake fluid feed line opening. I just cut off the rubber hose from the pump and pushed that in the hole really hard.
It's not that much work getting the pistons out and the whole rebuilding process was the first work I carried out on my 911.
Good luck.
- Michiel