These are books that are freely accessible online.
These are books that you'll likely have to buy, or lend from a library.
Pre-packaged Lisp Environments
These are Lisp editing environments that are easy to install and get started with because everything you need is pre-packaged and pre-configured.
Common Lisp Implementations
This section lists some common CL implementations and their manuals. Unless otherwise noted, these are free software implementations. See also the Cliki's list of free software Common Lisp Implementations, and Wikipedia's list of commercial Common Lisp Implementations.