Computer Assisted Legal Instruction
Handbooks contain a comprehensive overview of relevant materials. These are most useful if used early and often to supplement class assignments.
Nutshells are intended to be a quick reference guide. They are great to refer to when one certain topic is troubling or when a broad overview is desired.
This is the link to the eBook version:
There is an inexhaustible supply of commercial products available, so it is beneficial to try to browse several and see which ones work best for you.
The University of Tennessee College of Law uses the Bluebook for citation format. You may buy a print or an online copy of the 19th edition of the Bluebook. There are also many useful guides on the Bluebook and how to use it.