There is a lot of great information out there about dog behavior and training. Here are a few resources that I recommend.
Books:
"The Other End of the Leash" by Patricia McConnell (All of McConnell's books on dogs are wonderful and highly recommended, but this is her most well-known.)
"The Culture Clash" by Jean Donaldson
"Don't Shoot the Dog" (and "Reaching the Animal Mind") by Karen Pryor
"The Power of Positive Dog Training" by Pat Miller
"How To Behave So Your Dog Behaves" by Dr. Sophia Yin
Websites:
Clickertraining.com
Dog Star Daily
The Whole Dog Journal website
This great dental health website was submitted by Anabel Kent:
http://dentalassociatesnova.com/guide-to-dental-health-for-your-pets/
I always love hearing about great websites and books - fill out the Contact form to share your favorites!