Great, but not for the beginner,
This review is from: Smashing CSS: Professional Techniques for Modern Layout (Smashing Magazine Book Series) (Paperback)
Customer review from the Amazon Vine Programme (What's this?)
I really find this book interesting, and it contains a lot of the information which you'll need if you want to learn CSS. It's quite a good accompanyment to the HTML5 book which Smashing Magazine also have published.
Where it falls down is explaining the different rules of how and why to write CSS into a CSS file. Which order should items be written in? How to do :before and :after css items. An introduction paragraph to how this is structured and a little history could help set the reader up a little better.