There is the installation guide that came with OS X Public Beta hardly what your looking for. You can find good information by just surfing the forums and posting messages.
As for a manual I'm sure we won't be seeing any orgazined book of sort until the release of OS X and even then they will probably just package a simple get to know the interface guide and nothing that dives into using the Terminal and settings up a decent web server. We'll have to leave that up to a third-party to write a book. Which usually happens with new Operating System quite fast.