Latex Manuals :

• Technical note on AMS-Latex (Download)
• AMS-Latex User Guide (Download)
• Using Imported Graphics in Latex 2e (Download)
• Essential Latex++ (Download)
• A Gentle Introduction to Latex (Download)
• Latex 2e for authors (Download)
• The Not So Short Introduction to Latex 2e (Download)
• Natural Sciences Citations and References (NatBib guide) (Download)
• A Latex style for slides and notes User's Guide (Download)

If you want to package your Latex Package, you will need this manual (Download).

Some what interesting material is also given in this dvipdfm User's Manual (Download).

I have found some interesting tips given in this document also (Download). This is nothing but about a forced Line Break. Tips are also given how to include page wide table and figures in two column format articles. Really it  works!!