[shassard]

Quicklisp (http://quicklisp.org/) is a great resource for Common Lisp libraries. While it doesn't have the huge volume of libraries that's available for Clojure, it's a quality, curated, easy to use source. Combining Quicklisp and SBCL give you a great toolset for getting started with Common Lisp development.

[TeMPOraL]

I agree. Common Lisp libraries also tend to be high quality and I'm sometimes amazed by the forethought and attention to details some authors have. Though I sometimes wish there were more libraries.