American Express is running a special offer through the month of April allowing cardholders to get $5 back on any $5 purchase through the iTunes music, app, or iBook stores. If you’ve got an American Express card and want to take advantage of the deal, you’ll need to opt-in to the offer through your account online.
Once you’ve done that, just make $5 worth of purchases on iTunes Store with your American Express card. You’ll see the money credited back on your statement during the next billing period. Unfortunatley not every user will be eligible for the offer. If you are eligible you’ll find the offer listed on your dashboard.