I looked for it too, because the book says so insistently: If you don't believe it, look for yourself.
While there is no pastor Danny or website for him, Colton Burpo who is mentioned in the book (a young boy who claims he had an out-of-body experience during surgery and visited heaven) IS real though.
It's funny, because I was just reading the book and the film based on his experiences (Heaven is for Real) just happens to be on tv here. Anyone seen it? Since it was mentioned in the book I will at least try it.