One of the books recommended by our breeder was "Goldendoodles: A Complete Pet Owner's Manual" by Edie MacKenzie. We got it off of Amazon. My husband and I enjoyed it very much and it has a lot of good info in it.
"How to behave so your dog behaves" by Sophia Yin. And Patricia McConnell's books "The other end of the leash" and "For the love of a dog" to help understand ourselves and our dogs better :)