Available Books
Leslie
Lamport, the original developer of the LaTeX set of macros for Donald Knuth's
TeX system, has written what I feel to be the best beginner's book on LaTeX. It
makes good compromises between gently explaining in detail how things work for
beginners, providing enough detail to compose fairly sophisticated LaTeX
documents.
Once
you've familiarized yourself with LaTeX using Leslie Lamport's book, the very
best book I've used on more powerful techniques is The LaTeX Companion,
by Goosens, Mittelbach, and Samarin.