Here's my list of recommended books for beginners.
If you want books on magick specifically:
"Earth Power" by Scott Cunningham (a very down-to-basics folk magick approach)
"Practical Solitary Magic" by Nancy B. Watson (magick presented in a more systematic way than Cunningham's book)
"Modern Magick: Eleven Lessons in the High Magickal Arts" by Donald Michael Kraig (like Watson's book but goes more in western ceremonial magick including Kabalah)
There are many more out there but if you read at least two of these three books you're off to a good start.
If you want books on Wicca (which is a specific religion that incorporates the practice of witchcraft):
"A Witches Bible" by Janet and Stewart Farrar (originally published in two volumes as "The Witches' Way" and "Eight Sabbats for Witches") This is considered by many to be must-read material for Gardnerian and Alexandrian Wicca. Janet Farrar and her new husband, Gavin Bone (Stewart Farrar passed away a few years ago) have a new book out called "Progressive Witchcraft" which is also very good but is a departure from some of the ideas they presented in earlier works such as "A Witches Bible."
"Buckland's Complete Book of Witchcraft" by Raymond Buckland. He also has a new one out called "Wicca for One" which is excellent from what I've seen so far.
"Wicca: A Guide for the Solitary Practitioner" by Scott Cunningham. This one presents how Wicca can be practiced without belonging to a coven or formal group -- the idea was highly controversial when he first published this book. Now the idea of solitary Wiccans is pretty mainstream and many other books take it for granted as acceptable.
"Witchcraft for Tomorrow" by Doreen Valiente. All of Doreen's books are excellent, but this one is a good one for beginners. Doreen was one of Gerald Gardner's first, and probably most influential, high priestesses. Gardner is credited by many with being the one who started (or at least started to promote) Wicca as an actual religion.
One thing to remember when reading about Wicca is that many of the historical claims, especially in books written prior to 2000, are highly suspect or even disproven. For a long time people claimed that Gerald Gardner was just passing on an intact pre-Christian religious tradition. As the result of a lot of scholarly attention in the past five or ten years, it is considered very likely that Gerald Gardner was the catalyst in taking bits and pieces of folk magick, ceremonial magick, classical Pagan ideas, etc. and putting them together into a coherent system which we now call the Wiccan religion. There are a lot of people too (like Alex Sanders) who claimed they were initiated by relatives into authentic pre-Gardnerian Wiccan denominations but to date none of these claims have held up to scrutiny. Alex Sanders' claim in particular was proven to be a lie. Despite the unproven claims of ancient lineage Wicca is a vibrant, workable system that is meaningful and effective for thousands of people. I'm Wiccan myself, and have been for over twenty years now.
The books listed here are again just to get you started and are some of the better beginner books I've seen. There are a lot more you can get into when you're ready to move on in your reading.
Have fun!