If you are not familiar with federal civil procedure, including the Federal Rules of Civil Procedure, it is helpful to consult secondary sources. Note: A practitioner is more likely to use one of the comprehensive multi-volume treatises (e.g., Federal Practice and Procedure, Moore's Federal Practice) which are available both in print and online. The multi-volume treatises are especially useful when you are searching for an in-depth discussion of a particular rule and want to find cases interpreting the rule.
Treatises:
Hornbooks: