there was a recent discussion about oxy/propane over on the framebuilder list. The bottom line was that the regulators and torches are the same. The only difference is that the bigger torch tips that you probably aren't going to use have a counterbore on the end that keeps the flame attached. I'll try to find a link tomorrow.

You might have to break down and go to the LWS to buy adapters. It's never a bad idea, the one around here is a chain and they have competitive prices.

This is the framebuilders list thread. Seems pretty clear that you can use an acetylene regulator. You will almost surely have to get an adapter to screw on to the propane tank. LWS should have that. The tank adapter screws into the regulator body; I just had to have mine replaced since it was galled to the extent that changing tanks was a real chore.