Agree with all of the above. One of the best resources you can get is a quality trainer. The trainer for our obedience classes gives us homework AND gives us a bunch of articles on training written by reputable animal behaviorists. A lot of this is stuff I couldn't find online without spending awhile searching.
This forum is a good resource, though as with all forums advice should be researched and taken with a grain of salt. Kastle's blog has helped me loads
Books:The Other End of the Leash
by Patricia McConnell Puppy Right Start: Foundation Training for the Companion Dog
by Kenneth and Debbie Martin Train Your Dog Like a Pro
by Jean Donaldson (have not finished this one yet but what I've read so far is great)The Thinking Dog: Crossover to Clicker Training
by Gail Tamases Fisher
Anything by Ian Dunbar (though I don't think all of his methods translate well to real life practice)
But me, I'm a better learner if somebody is showing me something. I can learn relatively okay if I read from a book but my largest improvements have been made from watching videos of trainers (Falon and Lies' videos), going to the schutzhund club, and meeting with a private trainer once a month to have my methods evaluated and see what mistakes I'm making.
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