Ubuntu: Knowledge Base for System Admins

I’m looking for a set of resources which would allow me to guide system-admins in the right direction when it comes to Ubuntu.

See we have a number of systems-admins are community centers, and I want to be able to offer them the resources upon request to learn about managing their centers with Ubuntu.

Sometimes this is just basic stuff like ‘What does a computer look like inside’ or ‘How does networking work’ wikipedia can answer some of these simple things.

But then you get onto more complex issues such as ‘How does PXE booting work’ and ‘What do I need to do to create an image of a machine setup’

If anyone out there in the community knows of an existing resource, then I’d like to hear it. Otherwise we’ll be trying to teach people on the fly as we go.

These are the sites recommended so far: