Richard,
The one I brought to our rifle building class was the one made by Narex that Jose linked to. It was a nice, fairly light beech mallet and was pretty cheap. I couldn't see a good reason to pay $80 for a Swiss made one. If I had a wood lathe I would have done what Mike did and turned one from a nice hard piece of scrap wood.
I think I saw this question once before and the general consensus ended up being that you should just try a few and use what works best for you. Hope you enjoy that carving class, I wish I was going to it.
K.C.