A while back, I mentioned it was one of my goals over the summer to immerse myself in learning everything I can about the new clays. Of course, I haven't even picked up a package yet. Heather and I do have plans to change this very, very soon. In the meantime, I've been surfing around for a bunch of online tutorials.
Metal Clay Academy has a ton of resources for Bronze and Copper clays.
Hadar Jacobsen's blog @ Art in Silver features a lot of info on all types of metal clay.
Lot's of metal clay eye candy can be found on Celie Fago's site
I'm sure there are a ton of others, but these links should give you an excellent starting point.