From 9to5Toys.com:

Update: You are too late for Best Buy but Walmart has that beat with 20% off $50 iTunes gift cards.

Screen Shot 2012-12-18 at 2.09.23 AM.

Today only, Best Buy offers the $100 iTunes gift card for $85 with free shipping (which will arrive before Christmas) or in-store pickup.  iTunes gift cards are good for music, videos, movies, iBooks, Mac and iOS Apps and much more.

Screen Shot 2012-12-18 at 2.21.17 AMNote: Sam’s Club has a $25 4-pack for $84.64 with free shipping for delivery before Christmas.