Object-Oriented Common Lisp - By Stephen Slade; Prentice Hall PTR, 1998, ISBN 0136059406. Likely the best book available on using a CL environment for uses other than AI programming. - http://www.phptr.com/bookstore/product.asp?isbn=0136059406&rl=1
Common Lisp: A Gentle Introduction to Symbolic Computation - By David S. Touretzky; Benjamin-Cummings, 1989, ISBN 0805304924. Fine introduction for beginners; even one who never programmed before in any language will be able to use this book, yet covers all relevant topics thoroughly. Full version online, two forma - http://www.cs.cmu.edu/~dst/LispBook/
Practical Common Lisp - By Peter Seibel; Apress, 2005, ISBN 1590592395. Focus: putting CL to practical use with example projects: spam filter, ID3 parser, Shoutcast server. Source code downloads. Full version online. - http://www.gigamonkeys.com/book/
ALU: Lisp Books - A bibliography of Lisp books from the Association of Lisp Users - http://www.alu.org/table/bibliography.htm
The Common Lisp Cookbook - Collaborative project; goal: write for CL a work similar to O'Reilly Media's Perl Cookbook. - http://cl-cookbook.sourceforge.net/
Best Lisp Books - A variety of books on Common Lisp programming and AI, personally chosen by an experienced developer. - http://www.apl.jhu.edu/~hall/lisp-books.html
On Lisp - By Paul Graham; Prentice Hall, 1993, ISBN 0130305529. Thorough study of advanced methods, with bottom-up programming as unifying theme. First full description of macros and their uses. Covers important topics related to bottom-up programming: functional p - http://www.paulgraham.com/onlisp.html
Common Lisp: An Interactive Approach - By Stuart C. Shapiro; W.H. Freeman, 1992, ISBN 0716782189. For advanced CS students, undergraduate and graduate, stepped tutorial, many exercises and assignments for hands-on learning. treats functional before imperative programming, covers CLOS. Full ver - http://www.cse.buffalo.edu/pub/WWW/faculty/shapiro/Commonlisp/
ANSI Common Lisp - By Paul Graham; Prentice Hall, 1995, ISBN 0133708756. Tutorial introduction of essential Lisp programming concepts, plus a convenient, up-to-date reference manual, for ANSI CL. - http://www.paulgraham.com/acl.html