TenkoTAiLS: I wonder why GOG hasn't made any partnership with Epic or iD yet? Is love to see Commander Keen on here, Jazz Jackrabbit, One Must Fall, we are missing a lot of the old Appogee stuff too considering Duke 3D was licensed from them. Where's the earlier Dukes, Cosmo, Monster Bash etc there's still a ton of older titles that some studios are holding onto that aren't on Steam either.
Yes, those games were my childhood. All of them, I am constantly hoping GOG gets them, everything in your post would be an instant buy!!!
Oh, but Duke 1 & 2 are here, I own them:
http://www.gog.com/game/duke_nukem_12