Please anybody can correct me if i'm wrong, but i think the retro costumes are distributed this way:
Male Ninjas:
Amazon: Reptile and Ermac, plus Reptile classic fatality (by consensus in a thread i've opened earlier this month the classic fatality is most like the MK2 one where Reptile eats the head of his opponent with his tongue).
Gamestop: Scorpion and Ermac plus Scorpion classic fatality (probably his MK1 or MK2 Toasty)
Best Buy: Sub-Zero and Ermac plus Sub-Zero classic fatality (most likely his MK1 Spine Rip)
Female Ninjas:
Wal-Mart: Mileena, not Molina, as their preorder page says

(Classic Costume only, apparently no Classic fatality included)
Mortal Kombat Blu-Ray Movie: Jade (Classic Costume only, apparently no Classic fatality included)
No Kitana Classic Costume has been announced, at least to my knowledge, again, if anything i've said is wrong please don't hesitate to correct me.