Here’s a series of well written IBM Linux tutorials to help you learn Linux fundamentals and prepare for system administrator certification. The LPI prep tutorials help you prepare for the topics in LPI exam 201 and the topics in LPI exam 202.
You can find more about the certification at the Linux Professional Institute.
I’ve been meaning to take LPI 201 for quite sometime actually, it looks like a pretty solid foundation to Linux and I know most of it allready, so I should be able to do it without too much problem.
You can find the material at IBM:
The eight tutorials below help you prepare for the eight topics in LPI exam 201. Exam 201 is the first of two LPI intermediate-level system administrator exams. Both exam 201 and exam 202 are required for intermediate-level certification, or LPIC-2.
You do have to sign up, or just use Bugmenot, the bugmenot extension for Firefox is very useful ;)
To any budding hackers, yes it is recommended you have strong Linux skills.