I bought the book the other day after it was posted here: http://news.ycombinator.com/item?id=1836935 and have been working through the chapters. The book contains some CLISP specific code but I'm running SBCL. So this is my SBCL hack for the first stumbling block I found.

disclaimer: I'm a LISP noob, so this is a beginners hack, but it may help others (like me) who have had difficulty installing CLISP.