Hi Rod
Which material depends on the effect you are trying to achieve. I also am just learning. I just bought a kit from MicroMark, which contains everything you need to get started. It retails for around $99.
I originally started with an Alumilite kit from Hobby Lobby, but found it difficult to use. The MicroMark stuff is mixed on a 1:1 ratio, and should be easier than the 1:10 ratio Alumilite uses. From what I have read, the MicroMark is also more durable.