"Running Linux" by O'Reilly is pretty good when you're starting out and still a handy reference if you're stuck. It's not specific to a particular distro and it's very readable.
(no, I don't work for O'Reilly)
Most (some?) distributions ship with documentation on the CD's - how-tos from www.tldp.org
etc - check /usr/share/doc (s) to see what you've got. If there's nothing there you should be able to install them from CD.