Pre-order Sofia the First: Once Upon a Princess for $13.86. It releases on March 5 and if you pre-order now, and the price goes lower, Amazon will give you the lowest price. I love to do pre-orders with them because I don't have to watch prices. They'll just automatically drop the price for me if it drops on their website.
You can also Save $6 when you pre-order Sofia the First: Once Upon a Princess with an eligible Disney Junior Title. The eligible videos include Jake & the Never Land Pirates and Mickey Mouse Clubhouse.