We send all of our phone books to the recycling center to be made into next years book, if they even do that. Maybe it turns into my next cereal box. I don't know what they really do with them but create more waste I don't want in my life. I searched the web for an opt-out form on one of the publishers websites, but they don't have one. I did find a list of phone numbers you can call to opt-out of your next phone book. I have no idea if these really work, but I have called each and asked them to send mine to an old lady next year so she can use it to see over the steering wheel.
For AT&T the number is 1-800-792-2665. For Yellow Book the number is 1-800-373-2324 or 1-800-373-3280. You can get more info at paperlesspetition.org.