The paper versions are still available in the US but I expect that they are out of print. For the Belgariad V.1 HB-$52.75 on Amazon, Pawn of Prophesy MM PB only 10 left in stock. Looks like they are selling the last of the previous print run.
But yes, those books are probably not lost in copyright limbo just temporarily out of print in both paper and electronic versions. But it could easily happen if authors don't make provisions in their wills for their book rights.