What type CNC punch presses are you interested in? I have not found any punch press specific forums. Have you tried the Yahoo groups? I have considerable expereince with the Amada CNC turret punch presses, and am currently operating one of the newest Amada turrets(EMK3610NT). I believe it has the highest hit rate available or at least it did when it was first released. I had hoped to find more information available here in regards to punching and CNC punching in particular, but have not seen a lot yet here.
If you find something I would be interested in the same.