Please make sure you were using a valid American Express, Mastercard, Visa or Discover card. And also, please be sure you are using your *billing* address for the card (sometimes people put in their mailing address instead). Please note on some of our products, we have an option for PayPal payments (which allows you to use even more credit cards & a checking account if you choose).
You can also send payment via a money order to the address found on the order page.
If you continue to have problems, please use the "Contact Us" option on this page and let us know. We'll do everything we can to help you.