is there any one book you can read that could turn you gay?
Nope. But there are a lot of books that make men and women "curious" about homosexuality, and cause a lot of people to lean towards experimentation... usually, if a person stays gay or lesbian after experimentation, they've come out.
After all.. why CHOOSE to be something that isn't exactly welcomed in society? It's much much harder to be gay or lesbian than it is to be straight because of the extent of persecution faced by homosexuals daily. ...
.. but... if I had to guess on that book thing, anything by the Watchtower, if prolonged exposure occurs, could probably turn a person gay... after all, it damn near kept me straight...