That you knew what she was going to do and let her get away with it....not good. Doesn't take raising your voice for them to know just how serious you are. I don't necessarily even address the provocative stuff (the "I hate you", "you're the worst Mom ever" door slams etc). When I do, it's more about "I love you". If you give attention to the behavior you want...that's what you get.
Consequences for all behavior is the rule of thumb. Some of the consequences are good ones, some, not so much.
Also, when we "know" whether we do or not we telegraph it to them.
If a class would work best for you, by all means go for it. Where I am the libraries have DVD's and books on CD's too. I have found both helpful and b/c of limited time, I canlisten on my commute.
