These books contain storys about using human inner power. I'v read them all.
Castaneda was an anthropologist. He is talking about stuff what happen after he met old indian shaman in Mexico.
Well, many people think everything Castaneda said is a lie, that these books are full of fantasy and he made all storys up. I don't know what to think about that. Fact is, these books really inspire lot of people including myself.
I think its easy to find them in your local library.
If you enjoy or enjoyed Harry Potter, then I'm sure you enjoy Castaneda too.
If you already know about him, then hit a comment about what you think of his books and storys.
Internet is full of "how to use Castaneda books practical side, how to Lucid dream, how to defeat your EGO" etc. There are also groups of "followers" around the world. They call these techniques a Tensegrity. I'v been in a Tensegrity group but I wasn't sure, this is the "Thing" I seek, so I just quited being with them. I can't say anything bad about their attempts, because just sitting and doing nothing isn't better.