If you want to learn how to write your documents with LaTeX,
this introduction is for you. It is not about setting up a
LaTeX system. While it is not as comprehensive as Lamport's book,
it should be sufficient in most cases.

Rebuild the whole document from scratch by LaTeXing
lshort.tex. (If you don't have the AMS classes installed, the
relevant parts of the document will be left out, but it
will format without problem. After latexing the document twice, 
you should use makeindex to generate a new index file.