Those are all good resources. On top of that, Xach just posted[1] the number of times that libraries have been recently downloaded from quicklisp. I have been having fun checking out the most downloaded libraries.
I prefer common-lisp.net for finding a project's webpage and mailing list, but cliki has a useful section that lists projects by category.
Making some enemies: Google "common lisp" and you will find that link in the first page of results.
In a general programming languages forum this could be maybe ok.
But having this in the first page of HN (known for having some familiarity with CL) strikes as something superficial to me.
http://common-lisp.net/
http://www.gigamonkeys.com/book/
http://www.lispworks.com/documentation/HyperSpec/Front/index...
http://www.quicklisp.org/beta/
and #lisp on irc.freenode.net