If you're looking for an inexpensive pre-made solution for bending edges...
It comes with a 4", 3" 2" and 1" die which can be swapped out to give a lot of options. I haven't built a pair of skis using it yet but the test edge I bent today looks good. It can be found at Northern Tool (Jumbo Rod Bender). Northern also sells on Ebay. Check out the photos below.
I'm at the end of ski racing season so I haven't had much time to play with it, but the few short test pieces I tried, did twist a bit. While it's pretty easy to take the twist out, I'm thinking I can mod it a little once I figure out the exact cause; either by bolting down the main die or holding it flat at the feed pin.