What happened to this game? It's gone from Fantasy Flight's site and DriveThruRPG

By Citizenkane, in The Extraordinary Adventures of Baron Munchausen

Aside from physical copies still available on Amazon, is there any way to purchase this game? I'm looking for a (legal) digital copy, but haven't found it available anywhere online.

Odds are the licensing agreement ran out. Without a license in place, FFG (and by extension DriveThruRPG) can no longer legally sell copies of the game, especially not PDFs.

The stock that Amazon has probably isn't covered under the above, as any money that FFG would have earned has already changed hands, much the same as buying an out-of-print book from your local gaming shop.