I found one website that seems to lay out all the UNIX basics out in easy to understand fashion:
UNIX / Linux Tutorial for Beginners
If your looking for help that's specific to Debian (on which Voyage is based), then Debian Help is a good site:
debianHELP | Militantly FREE software support.
If you would like to get started playing with Linux, you could download Ubuntu and play with the Live CD. It boots everything into RAM; doesn't touch your hard drive. You could install from the same disk later on if you would like. It's also based on Debian
Ubuntu Home Page | Ubuntu