I've recently bought 2 books about pmc. The first is called, ' Inventive Metal Clay for beaders'. it's by Irina Miech and is published by Kalmbach Publishing Company., the ISBN number is 978-0-87116-258-8
The other book is ' precious metal clay techniques edited by Tim McCreight published by A&C Black of London The ISBN number is 978-0-7136-8757-6
I found the second one is more for students who have knowledge of pmc. the first is as it says, for beaders, which I am. It's very good. I found the pmc website very helpful as well. Just type in precious metal clay and off you go.