Resources for beginning Linux administrators

I've just acquired a dedicated linux server which I plan to use to deploy projects and host a few sites from. Unlike virtual or shared hosting services I've used in the past in this case I'm actually in charge of the entire machine and its configuration! And right now that seems like a daunting task.

Still, I'd like to learn more about linux administration and learn as I go, but preferably I'd rather learn from other people's mistakes and not my own. ;)

What resources, tutorials and first steps can more experienced administrators recommend the linux newbie admin as they make they make their way into into the wilderness?

Some other ServerFault questions and answers I've found useful so far:

• Should we disable the root user?
• How do you setup ssh to authenticate using keys instead of a username-password?
• What useful things can one add to one’s .bashrc?
• What are some informative and useful shell prompts? (bash, csh, ksh, etc.)
• Securing a fresh Ubuntu server

I'd start with a good book covering common administrative tasks for your OS (CentOS, by the look of the tags, which I don't have any documentation experience with). If you want to be a good Systems Administrator, rather than "good at admining this CentOS box here", then you really must get a copy of "The Practice of System and Network Administration", 2ed, by Limoncelli, Hogan and Chalup. It'll teach you practically everything you need to know about administering systems, from a conceptual level.

Setup a Virtual Machine (VirtualBox, Parallels, VMWare, Virtual PC) with a Linix distro and start playing!

By using a VM you can fiddle to your hearts content without worrying about breaking things. If you have a problem - just restore a VM backup and start again.