ANSI Common Lisp from PG gives you a basic overview of the language, has some examples and has also a short reference section. It doesn't teach you anything use

ANSI Common Lisp from PG gives you a basic overview of the language, has some examples and has also a short reference section. It doesn't teach you anything useful about the eco-system, IIRC. Practical Common Lisp teaches the language a bit more by example tasks...