blindfaith^_^
While I find misinformation annoying, I don't think that books can be blamed for this problem entirely. I mean people buy them because they say whatever that person wants to hear, which often times is a whole lot of nothing, but a "you're very special and elite" nothing all the same.
I don't think that's really true though, I'd say about 90% of the people buying these books, have absolutely no clue what it is that they are picking up. They've read something on the internet, seen a movie (or a show on tv)... said "ooohhh that looks cool", and then they order the first book that pops up on Amazon.com when they type in Wicca or Witchcraft. They don't know enough about what it is they are looking at, to even make a decent informed decision.