Web: <http://lispcookbook.github.io/cl->cookbook/>
Repo: <https://github.com/LispCookbook/cl-cookbook>

I like it a lot. The "Multidimensional Arrays" and "Loops" sections are
especially thorough.

Also this O Rly book :D
<http://lispcookbook.github.io/cl-cookbook/orly-cover.png>