Big things going on in both Marvel and DC, can't really speak for Marvel, but all the post Crisis stuff in DC is a pretty good place to start. Even better, Brad Meltzer (crime writer and excellent writer of comics) is now writing the new run of JLA, I just picked up issue zero, and it ain't half bad.
That's not even getting started on the ludicrous amount of wicked stuff coming out of Image at the moment. I'm not so up on Indie stuff really, I just pick up what I like the look of, but I'm sure there is a resident expert.
So do it, go buy comics, read them, love them. Joy.