There are finally more and more resources available to learn how to read dogs and they are available online.
Good 2 way communication can prevent bites and improve your relationship with your dog.
Here's a few:
Facebook group : Observation Skills for Training Dogs
Dog Ibox has two webinars on observing dogs www.dog-ibox.com
Fenzi Dog Sports Academy www.fenzidogsportsacademy.com
has at least 3 courses:
Dog as a Second Language
BAT (behavior adjustment Training)
stress in the ring