16:  Where can I get documentation on Emacs Lisp?

  Within Emacs, you can type "C-h f" to get the documentation for a
  function, "C-h v" for a variable.

  For more information, obtain the Emacs Lisp Reference Manual.  Details on
  ordering it from FSF are in file etc/ORDERS.

  The Emacs Lisp Reference Manual is also available on-line, in Info
  format.  Texinfo source for the manual (along with pregenerated Info
  files) is available at

    ftp://prep.ai.mit.edu/pub/gnu/elisp-manual-19-2.3.tar.gz

  and all prep mirrors (See question 89 for a list).  See question 17 if
  you want to install the Info files, or question 18 if you want to use the
  Texinfo source to print the manual yourself.

  A WWW version of the Emacs Lisp Reference Manual is available at

    http://www.cs.indiana.edu/usr/local/www/elisp/lispref/elisp_toc.html