With an older system you may want to try xbuntu. it is a lite version
made for older systems.
Tthe great thing about all flavors of Ubuntu, there free. you can
download them. burn the iso, and you have a full working distro.
you also can order them right form the web site and receive a copy as
well.

If you run into problems there are always forums here or on the Ubuntu
site :http://ubuntuforums.org/index.php . there you can find anything
Ubuntu.
I believe there are no books on Ubuntu because it has s quick (6-8
month) distro cycle.

oops almost forgot the live version is so you can load the real thing
on the system. it makes a temporary spot on your disk for a swap area
then runs partly form the cd. nothing loaded for good unless you tell
it to.