Amazon has the Oz the Great and Powerful Blu-ray / DVD + Digital Copy set available for preorder with a special $5 off coupon. The set retails for $44.99 but is available for only $31.49 – $5 off coupon. As with all Amazon pre-orders, you are guaranteed their lowest price up until release day, and they will automatically refund the difference if they drop their price.
Just look for the “clip this coupon” box to get your $5 off savings.
