I'm working on a MASON manual which will detail more or less every
feature of the system at present. Unlike the ECJ manual, which is
just that, I'd also like to have one or two tutorials and a bit of
discussion about agent-based simulation. Anyway, I've put out the
first chapter and a running (far from final) title. The first chapter
is a tutorial largely cribbed from the WCSS 2008 tutorial. Thought
you might be interested.
http://cs.gmu.edu/~sean/temp/mason.pdf