Well, the obvious choice is to get started on the Dark Tower novels, beginning with "The Gunslinger." They're of uneven quality, as is often the case with King, but I think that in the end he brings it off quite well.
As for the Stand, I recently re-read it myself, and I admit I liked it better the second time through. My main problem with it the first time was the LITERAL Deus ex Machina ending. But I think the second read through made me more sympathetic to it because he clearly builds up the thematic element of sacrifice for the sake of others, and the fact that all of this is ultimately out of the protagonists' hands. Though it still grates a bit, because, after all, if the resolution of the action is out of the hands of the protagonists, what the heck are you reading about them for? Is this a Beckett play?