casting resin?

[oneautumnday.livejournal.com]

I'm going to be ambitious this summer and learn to work in resin so I can make a pendant for a cosplay costume I'm making. The pendant, just so you have an idea of what I'm going for, can be seen here, circled in red. I'm sure I can make the gold bits in sculpey as I'm quite good with the stuff, but it's the clearish pendant itself that gives me trouble.

Problem is, I know little to nothing about casting resin. I know that you can make a mold out of sculpey and that if you get clear resin you can paint it with acrylic and it will stay fairly transparent. That's about it.

Would Michael's craft stores carry it or will I need to take my search online to find the supplies I need? Actually, all I really need is a place to find the resin itself, for casting, and instructions on how to make it take shape (heat? or something else?). Any help or points in the right direction would be immensely helpful. Thanks!

(x-posted in cosplay, cosplay_help, craftgrrl)