Nice haul. I've got the two same Burroughs editions, myself.
I have that edition of 'Pellucidar,' too. Love the cover art of 'Lost on Venus.'
Been cruising good ol' Bookman's, I bet.The one near my house had a near-complete run of the Thongor series (and also a boxed edition of the old Thieves World RPG, which I, like a moron, failed to snatch up).