well personally i would say, save yourself the 100 dollars and just read ...
so with that said i would say the best source for learning linux, and the best
source for everything else, is
www.google.ca i am not trying to be sarcastic
but its the truth ... just search for stuff .... and to make it more "reliable and accurate"
use
www.google.ca/linux ...
and i dont' know what you want to learn, or where you want to start but i will
link a few things to get you started ...
http://www.icon.co.za/%7Epsheer/book/rute.html.gz
(from beginning to end - READ THIS - highly recommended)
http://www.onlamp.com/linux/cmd/
(commands dictionary)
http://www.qvctc.commnet.edu/classes...nux_files.html
(filesystem breakdown and explanation)
http://www.debian.org/doc/packaging-...s-toc.html#TOC
(a more detailed look at the filesystem)
http://www.tldp.org/tldp-redirect.php?url=/
(TLDP - the linux documentation project - contains all the HOWTOS)
http://www.unixguide.net/linux/linuxshortcuts.shtml
(shortcuts and commands)
http://www.sorgonet.com/linux/shortcut/index.php
(a couple more shortcuts)
http://www.dclug.org.uk/linux_doc/tips.html
(20 Linux tips)