I found Bill Kramer's book to be very helpful in really understanding how the lisp language for AutoCad works. I would not say it is for the absolute beginner. It does not contain tons of non-useful, simple code to use as a tutorial. It does, however, contain a lot of truly useful functions and detailed explanations on how the code actually works. From the very start, it discusses how to use AutoCad's Visual Lisp Integrated Design Environment, one of the best tools for helping programmers write functions. This is something other books, inexplicably, leave till the end. I highly recommend this book to anyone. It is one of the better books out there.