The sites listed below all have some excellent guidelines on training and solving behaviour issues.
The number one best approach is to get into at least one good, positive approach (eg rewards-based, non-punishment, non choke chain/prong collar) obedience class as soon as you can with your puppy (usually 4-6 months onwards). A class has numerous benefits for your cavalier, from socialising with other dogs and people to teaching your dog to listen to you even in a setting full of distractions. PLUS, it's FUN!! And no dog is too old for classes -- you can always teach old(er) dogs new tricks!
But a class won't teach everything -- and we all have ongoing questions, new issues arise, and we think of new things we'd like to try with our dogs. Hence this listing of advice sites. Some have files that are handy for downloading and printing for reference.
Good starting point: HOW to train a dog and why NOT to punish, including during housetraining, if you want your dog to learn. And this quickie overview on how to get the dog you want.
Trainer Dee Ganley on Behaviour:
... and on Training:
Plus her highly recommended training manuals for purchase:
Trainer and behaviouralist Dr Ian Dunbar:
Trainer Stacy's Wag'n'Train, San Jose:
The Pet Place Behaviour Library:
Animal Behaviour Associates:
Diamonds in the Ruff's Common Behaviour Questions and Training Tips:
The Positive PetZine has loads of training advice and techniques and Q&A too!