Java Developer's Guide to Eclipse
Book: "The Java™ Developer's Guide to Eclipse, 2nd ed."
Authors: Jim d'Anjou, Scott Fairbrother, Dan Kehn, John Kellerman, Pat McCarthy.
Publisher: Addison-Wesley Professional (book page)
Date of publication: October 26, 2004
Nick Edgar's opinion: Highly recommended if you are doing any development with Eclipse, whether for plug-ins to the IDE, or for other applications built on the Rich Client Platform. Many people developing RCP apps have told me they have found this book to be immensely useful.