So, you want to be a Witch. Well, I will tell you right now, that if you are here because you saw the movie "The Craft", and you want to learn how to fly, or to change your hair color without using hair dye, you are in the wrong place. That is not what Witchcraft is, that is what we call Hollywood and special effects. I already told you (kinda) what Witchcraft is. Here, I will tell you what you can do to be a part of this wonderful religion. Of course, there is much more to becoming a Witch than what I say here...this is just a starting point for you.
The first, and, in my opinion, most important thing you can do to begin practicing Wicca, is read, read, and read. You can not read enough...there is sooooo much information available out there, you would have to be pretty dumb to not be able to find any. Of course, there are also a lot of books available which will not help you much. There are many books which claim to expain Wicca, but do not. After a while, you will begin to know which books are legit and which are not. For starters, though, it is a good rule of thumb to not believe most of what you read...always be skeptical. Trust only what feels right to you. If killing and offering sacrifices to your gods is what feels right to you, then you should check out the Satanism section, for you will not find any of this in a 'real' book on Wicca.
The next most important thing to learning Witchcraft, is try to acquire a living correspondent, via e-mail is the best, and safest, way, as it is not really safe to walk around asking people if they will teach you to be a Witch. Having a person to talk to is great, as there will be times when you have a question that a book will not answer. Of course, there will also be times when a person cannot answer a question for you either. In this case, you would go to...
...the third thing that you can do to learn Witchcraft. Practice! As soon as you feel comfortabe with your newly-acquired knowledge (or the beginning there of), jump in and try holding your own ritual. Do not worry about about not having the right tools, or not doing things 'the right way'. Remember...there is not 'right' way. The God and the Goddess will not send down a bolt of lightning to strike you dead if you mispronounce a word, or use your finger instead of an athame.
Well, that should give you a good place to start. If, for some reason, you are unable to bring books on this subject into your house (Hey, I was at that point when I began), and you cannot find someone to communicate with, I am here.