I've only being using Linux for about a year now and I'm pretty good at it. But I want to become really good so that I can do all of my hosting on my own Linux box and make my own Distribution. Where can I find those hard to find Linux knowledge that turns an ordinary Linux user into a Linux Guru?

Experience turns a user into a guru.

The best way to acquire such experience is simply to do what you've been doing. Work on projects and work on issues as they arise. You learn far more from what goes wrong than what goes right.

Pick specific things you'd like to do then look for "how-tos" or "tutorials" for those things in Google searches. e.g. "apache tutorial" would be a good search for setting up a web server. Or if you want to do it the tried and true way you can buy the plethora of excellent O'Reilly books on various subjects, read them cover to cover and implement what you find there.

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