1) Major Public Databases
2) MeSH Vocabulary:organization of the database: (NLM document)
3) What is a search filter?
4) Combining Searches: Boolean logic
5) The Anatomy of a Search
6) Expanding and Limiting your search
7) Notation
8) A note on (not) using subheadings
9) Searching for a particular citation or for a related citation
10) Tips on searching for specific information types
Additional Resources

Ovid Online Search Manual
PubMed Overview
PubMed FAQ's
Grateful Med Users Guide