Buying 'Halo 3 ODST' on thehut.com help?

I pre-ordered halo 3 ODST on thehut.com because it was cheaper than play.com but on play.com it said that you get unlock codes for Sergeant johnson and a disk for 3 new halo 3 maps (heretic,longshore & citadel). Will i get these from thehut.com? & if i cant, can u buy them seperately? Thanks