My Daddy Snores by Nancy H Rothstein. There were more than I thought there would be. Here's some good ones.
• The Napping House by Audrey and Don Wood.
• Dinosnore! by John Bendall-Brunello
• Bear Snores On by Karma Wilson
• Stop Snoring Bernard by Zachariah Ohora
• Snoring Beauty by Rachel Mortimer
• Snorey Time by Meg Pybus, which strictly speaking isn't about snoring but about not wanting to sleep and many a parent wants what this book has to offer.