Well coincidentally, I've been dubbed the Actionscript 3 expert at my old workplace. However I already left to start things on my own.
I would love to help with actionscript 3, maybe I'll post some resources soon and make sure you're updated on that.
DX and OGL are really a hard investment to make, and for the inpassionate: a really painful one, and possibly an infruitful one. I am already trying to catch back, not a nice experience.
Actionscript though is almost immediately rewarding and much fun to work with, if you're just starting, I'd say please stay, and here in this market of Lebanon, you'll really make more than the usual developer if you know what you're doing (fact).
First steps: Download FlashDevelop. The single most important thing to work with. Gives you a first-class IDE to work in instead of that bullcrapAadobe thinks is an IDE (Flash). You can also get FlashBuilder from Adobe, but that's not free.
http://wonderfl.net is the jungle. If you're reading books about a safari in the jungle, well who needs that if you can access the jungle itself. Hope you got what am trying to portray. And it has a compiler all of its own, on the web.