Found an interesting Emacs blog with lots of tips and tricks, and 
is run by Ryan McGeary.
The entry for running Emacs on OS X is useful. Ryan recommends the Carbon 
Emacs package, which is a pre-packaged version of the GNU Emacs version 
22, and contains a ton of extra packages not available in the CVS Version.
I personally use the latest Gnu Emacs Version 22 from the CVS repository, and compile 
the application manually (well, via a cron job actually) every month or so, to keep up with the 
latest developer changes being made in the code-repository itself (which – BTW – can be tracked via 
the Emacs devel newsgroup), and prefer to manually setup the packages I need.
Apart from the literally thousands of site on the net dealing with Emacs, one 
wiki Site I can whole-heartily recommend is the Emacs Wiki: 
http://emacswiki.org/, a fantastic resource on Emacs of all 
varieties, and catering users from newbies through über-geeks.