Read LICENSE. It's a 2-clause BSD license, but you should read it anyway.
If you're upgrading, read RELNOTES. There is also much documentation at http://supybot.com/ for your perusal. Please read it; we took the time to write it, you should take the time to read it.
If you have any trouble, feel free to swing by #supybot on irc.freenode.net or irc.oftc.net (we have a Supybot there relaying, so either network works) and ask questions. We'll be happy to help wherever we can. And by all means, if you find anything hard to understand or think you know of a better way to do something, please post it on Sourceforge.net so we can improve the bot!
The wizards (supybot-wizard, supybot-newplugin, and supybot-adduser) are all installed to your Python directory's Scripts. What that probably means is that you'll run them like this: C:Python23python C:Python23Scriptssupybot-wizard
We likewise have tons of developer documentation at http://supybot.com/ for your learning adventures. Have fun :)