More on the historical front
As you might have noticed, an anonymous comment on the post immediately below this one pointed the curious to Pristine Classical, whose downloads include (some) of the Music & Arts discography. Pristine also has some interesting releases on its own, like that 1939 Mengelberg Mahler 4th, with Jo Vincent, which has been floating around for some time (and has attained some measure of popularity).
It's an interesting site with some interesting music. The problem, of course, is that it's priced in the euro, which means - if you're an American - you'll take a bit of shellacking on the exchange. Vissi d'arte, I suppose, right?