Q: Itunes credit card trouble.

Hello

Thanks for using Apple Support Communities.

Change or remove your payment information from your iTunes Store account (Apple ID)

http://support.apple.com/kb/ht1918

You can see the payment methods that the iTunes Store accepts in the Payment Type section. If you want to remove the payment method, select None in the Payment Type section. See what to do if None isn't showing or you can't select it.

Have a nice day,

Mario