"Making the Jump" from beginner AS to OOP

I’ve been teaching myself AS for about the past 6 months, as I’ve had time, and I feel like I have a good grasp on the basics. I’ve been through a ton of the tutorials on this site, including the AS/XML ones, and I think I’m ready to take the next step…

I always hear people talking about AS2.0 and 3.0, using OOP and classes and whatnot, and I really want to dive into that level of ActionScripting… So here’s my question: Does anybody have any suggestions for studying/practicing/learning these more advanced AS techniques? Put me in, coach!

Thanks!