Before heading down this path, consider using Emacs Live, which is a nice set of defaults for working with Clojure, Overtone and Quil.
Also, check out this nice write-up on debugging with nREPL.
I also drew inspiration (copied things) from Ryan Neufeld's config, which you should also consider using.
Finally, you can check out my ~/.emacs.d/init.el
config on GitHub.
All this as of May, 2013...