I've got the zbrush demo and I've been trying to use it, but I just can't seem to get anywhere with it.
I think a lot of the problem is not knowing what the controls do, or knowing how to use the program. But going to zbrush forms does sound like a good idea. I'll go and look on there soon.

Eventually (I realise it will take me a long time to get there), I'd like to be able to build an animal and animate it, so from what I've read maya would be better for that. Most of the things I'm wanting to sculpt will be organic shapes like creatures, but I'm happy to build it up from other shapes, rather than carve it away. I'm better with real media sculpting than I am with carving anyway, so it's probably an easier approach.

Can anyone recommend any really really basic tutorials for someone who has never used maya? Even the basic ones I'm finding assume some prior knowledge, or use terminology that is very unfamiliar to me. Something so I can get used to some basic tools and functions. At the moment I'm feeling pretty overwhelmed.