Chicago Manual of Style Documentation - A brief guide to the Chicago Manual of Style rules for documentation. It covers some of the more commonly used categories.
http://www.fsu.edu/library/explore/guides/chicago.shtml
Bedford St. Martin's Research and Documentation Online Resources - Provides examples of different sources and their correct citation.
http://www.dianahacker.com/resdoc/
Strunk's Elements of Style - A composition handbook intended for the study of literature, but provides the principal requirements applicable to film criticism as well. Concentrates on the rules of usage and principles of composition most commonly violated.
http://www.bartleby.com/141/index.html