To get started there's a "quickstart.txt" document in the root Java
directory. Once you've got that far, then get Eclipse up and running
(I see you've been working on that in your other post). There is a
fair bit of Javadoc that can help guide you and then the sample and
tools code can show you some of what you need to do.
More extensive documentation is definitely something that needs more
work though. We felt it was better to get it out sooner rather than
wait on that happening.
Stuart