Are you looking for documentation on how to do everything you would want to do with the server, including the following: concepts, checklists, "how to", best practices.... and is extremely organized with cross referencing, index and search capability and won't cost you a dime?
Start>help
I have books at home that span several feet accross on the subject you ask and to me, the help in windows is the most usefull. If I could make any other recomendation, it would be a windows 2000 server book.
As for my personal recommendations on what to do next, I'd follow the windows 2000 server book as a guide as they typically have labs built into the textbook where you do hands on configuring the server.
A+/MCP/MCSE/MCDBA