DrPetter (creator of sfxr) had just released version 1.0 of Sculptris today, and there's also an accompanying video which demonstrates some of application's features and sample 3D models that other users had made with the sculpting tool.

Anyone can start sculpting models by playing around with the basic features of the application, but it will take a bit of experimentation and reading up to learn how to use Sculptris effectively to create great-looking 3D models. The included documentation file has a detailed rundown on the interface, buttons, and shortcut keys, and you can also head on over to the Sculptris forums to post your questions there or just to showcase your works.