I installed leiningen and ran lein swank,
Aquamacs has everything about SLIME, so it\'s OK.
I found that I needed this in my .emacs to get it to work:
(eval-after-load "slime"
'(progn
(slime-setup '(slime-fancy slime-asdf))))
I had the same problem if I used (slime-setup '(slime-fancy)). Changing it to (slime-setup '(slime-repl)) fixed it.
I found this the easiest setup for the latest version of everything. Here's a quick summary where I"m assuming you have leiningen installed.
Install the swank-clojure plugin
$ lein plugin install swank-clojure 1.3.2
Create your clojure project
$ lein new test-project
$ cd test-project
$ lein deps
Then open one of the clojure files from your project in emacs and run clojure-jack-in
M-x clojure-jack-in
You are now in a slime buffer with clojure and the dependencies for your project loaded.