Since so many opinions these days seem to be based on anecdotal evidence, let me add another anecdote to the mix.
I am sitting in a coffee shop near where I live doing e-mail and so on. In walks a very stylish young woman, no older than 30. She gets a coffee, sits down and pulls out a Dex companion print Yellow Pages directory and begins flipping through it to make calls arranging some sort of project for her house.
So there you have it, print Yellow Pages is alive and well. No further evidence is required.