I could have written your comment! My father bought me that book when I was about 16 or 17 years old, as a birthday gift. At the time, I too was an atheist, but not a very skeptical one, and TDHW had a huge impact on me.

That book is one of the only gifts I can remember recieiving when I was a teenager, and I still have it on my shelf. It is fair to say that it can be a life changer.