I really like Winston and Horn's Lisp. It actually is written assuming you don't know how to program at all, but quickly moves along into more complex stuff, really showing off what Lisp can do. Winston teaches (taught?) at MIT, and when the book was first written I guess it was still a reasonable possibility that you could be a freshman at MIT in computer science and have never programmed before.

http://www.amazon.com/Lisp-3rd-Edition-Patrick-Winston/dp/02...