I'm assuming you are using Quicklisp to load code from the book Practical Common Lisp. To load code from the book, you need to use the "load" function. For example, to load the code from Chapter 1, you would use the following:
(load "book/chap1")
You can also use the "load-file" function, which will load a file from the filesystem. For example, to load the file "book/chap1.lisp", you would use the following:
(load-file "book/chap1.lisp")