If you're really interested in training, I'd recommend considering the clicker, you could start off with "Clicker training your dog" by Karen Pryor, excellent with colour photos, and Jo Hill's Motivation Movie video :)
If you're not keen on the clicker idea, i'd recommend attending a good pet dog training class, try one run by the Assocation of Pet Dog Trainers, www.apdt.co.uk for starters.
I'd also recommend a book called "The Complete Idiot's guide to Positive Dog training" by Pam Dennison which is very good indeed.
I'd also suggest, reading Dogs Today and Your Dog for interesting training and behaviour articles.
For understanding dogs generally, do try "The Culture Clash" by Jean Donaldson
Best of luck, let us know how you get on!
Lindsay
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