A Title Much Cooler Than Anything on the Old Site
I disagree with WotC lore being "terrible" and would rather not throw out my books, but I'll definitely check out Draconomicon.Go with 3PP books really, and throw out WotC lore books - it is terrible anyway.
Dragons = Draconomicon. This is really an amazing book
Then just go for setting books, but make each setting its own meta-plane (Primal Order books), akin to MtG, and then you are done.
I'll have to see if I can find a copy at my FLGS's used-book session. Getting the used book on Amazon is very expensive. I hate reading books in PDF format, I just use PDF versions as easy reference during prep and in play.