Overall Linux Manual
Lots of good stuff out there. The Rute Document, TLDP, etc.
Generally speaking, however, it's useful to have in mind what one is after. Do you need a comprehensive reference, or do you need a solid curriculum? Two very different things. Some documents can and do serve as both, depending on how they're used. Might be useful to think about how you (intend to) use the material.
I think I have found FlatFish! Doesn't this guy sound just like the vertically challanged one? I am a musician. I spend a reasonably large proportion of my life creating and recording music. My...
Dipping in and out is an excellent long term knowledge booster, as it allows one to concentrate on discrete focuses. But that presupposes a basic comprehension of Linux, or *nix systems in general. On the other hand, a course of study doesn't address needful stuff of the moment, and so can't be relied on to return immediate value.
Most people acquire their understanding of *nix systems by osmosis (repeated exposure, including some amount of trial and error). A more efficient way is a course of study, and the Rute Document by Paul Sheer is intended for that purpose. If you suspect that you have holes in your grasp of the overall subject, doing the course as Sheer recommends may well be worth your while.
HTH
Longfellow
I think i have discovered who FlatFish really is
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