If you're looking for other books... For beginner books... I think if you really need a "reference" book as a foundation and nothing more, I rather like:
"The Tarot Bible" by Sarah Bartlett (it's more like a "Tarot Dictionary" than a "Tarot Bible" IMO, but it has all the card interpretations in *paragraph format* -- something which I feel is very important, as I feel snippets and keywords are really bad influences on a new reader -- and pictures of the Universal Tarot on every card page, as well as a host of stuff about How to Read, Spreads, etc). I bought this for my friend for Christmas, and she's been doing well with it.
There's also some merit to "Simple Fortunetelling with Tarot Cards" by Corrine Kenner. Again, it displays cards (though not in color like the Tarot Bible) and shows 3 sets of cards and describes them, along with paragraph-style. It has astrological and numerological information, too, but not in depth. It's a bit thin for an only reference, though. The same friend had purchased that one on her own, and I rather liked it when I flipped through it.
www.learntarot.com is also a great resource. I'm not sure about the book itself. I think the exercises are better than the information, which is sort of phrase/keyword based.
Once you get a little more adept, I rather like "Tarot for Yourself" by Mary Greer. A lot of Greer's books are "beyond the beginner" but I think this one works at every skill level, and it helps take you to higher skill levels. (I would save 21 Ways to Read a Tarot Card till you're a little more comfortable, but it's also very good.)
Also, just buying decks that come with good books always helps. I find some of my deck books to be some of my favorites (my Jane Austen Tarot companion book, my Fairytale Deck companion book, and the Llewellyn book are all great wells of inspiration, and The Book of Thoth really took me to a new level when I first read it---though if you're working with a RWS style deck, that's a bit of a tangent...but it might be a different deck book for you; I think those often 'spark' the most 'a ha!' moments, though, because they actually interact with the deck).
Personally, I would stay away from: Books with too many keywords. Books that focus on what a card means in a position. (Until you are very comfortable knowing what the whole card means and its entire spectrum in the first place.) Books that focus on a particular spread, especially the Celtic Cross. The latter 2 things aren't bad in general, but they just seem like 'skipping a step' if you don't know your cards well yet. I think before we can learn what cards mean in a Spread, we have to learn the cards and Spreads separately. Maybe just me.