The Emacs Reference Card (also available in in Postscript (printable) or Text format).
The Gnu Emacs Manual (the info pages). Many, many, more info pages are available.
GNU Emacs Frequently Asked Questions (split by question)
Emacs Implementations and Literature FAQ
From the FAQ: XEmacs is an alternative to GNU Emacs, originally based on an early alpha version of FSF's version 19. XEmacs was known as Lucid Emacs through version 19.10. Almost all features of GNU Emacs are supported in XEmacs (the ones that aren't supported are generally implemented in a better way in XEmacs). The maintainers of XEmacs actively track changes to GNU Emacs while also working to add new features never before seen in Emacs. The current version is 20.4, released on February 28, 1998.XEmacs has an Official home page which includes:
Emacs Lisp Archives:
Jennifer Myers <jdm at geek-girl.com> (Last modified: 2-Mar-98)