It's such an interesting name, and a very interesting taste too. In the U.S., fiddlehead ferns are mostly found in North-East and that too mostly in springtime. We saw them in Shimla, Himachal Pradesh also once, when we went there in May 2006.
Right now we have been able to find them often in the grocery store. But they'll go away in a few weeks. Since they have a very strong flavor of their own, I make them very simply, just salt and pepper. Wikipedia lists a slightly complicated process of making them. I clean the ferns by removing any black or brown parts and soaking them in water and changing the water atleast twice. Then simply saute them in salted butter (Amul butter). I mix a little bit of olive oil to prevent the butter from burning, add some more salt, and then add some water and cover it to let it cook. Once it's done I add pepper. And that's it. One thing I do like to make sure is that it is cooked in a single layer. Otherwise it'll not saute properly. Somehow we have never had any problems with food poisioning with the ferns, although I would not suggest feeding these to your child.