When it comes to finding a good book to read, I usually stick by picking books from the previous authors that I've read.
But usually, when I browse around in the bookstore trying to look for something, the books somehow calls to me.
Like when I first picked 'The Shadow of the Wind' by Carlos Ruiz Zafon, I've never heard of him. But when i saw the cover and held the book in my hand, i knew i had to get it and just start reading it.
I know this sounds corny and crazy, but that's basically how i choose my books