I HIGHLY recommend taking Love and Logic classes. Here are the list of classes the local Love and Logic instructor is teaching: http://www.keriparentcoach.com/447486.html Tell her T. sent you. You can also call the Love and Logic company at 800-588-5644 to get the contact info for people who teach classes in your area (I just called and a real person answered right away and was very helpful).
It is better to learn when the consequences for defying authority are relatively small.
The Love and Logic approach is all about tough love--being firm and consistent in letting children suffer the natural (logical) consequences of their actions, while doing so in a very gentle and loving way, having true empathy in your heart. My mom parented this way, and I really appreciate my upbringing. I feel she was a very effective and loving parent who helped prepare us for the real world.
If classes aren't available near you, check out some Love and Logic materials at the local library for free or buy them at www.loveandlogic.com. Here are some I recommend: a seminar on DVD "Painless Parenting for the Preschool Years," the book "Parenting with Love and Logic." They also have some great CDs full of wonderful advice and real-life applications that you can listen to in the car while driving.