How can I pay for Turbo Tax if I don't have a US based credit card?

Do you have a refund due?  If you do you can pay TurboTax by having the fee deducted from your refund.  There is a charge for that service.

For fee payment, we can only accept Visa, MasterCard, American Express, and Discover cards with a U.S. billing address.

Another option is to pay your fees with your federal refund, also known as Pay With My Refund (charges may apply).

Or....can you find somewhere to purchase one of those pre-paid debit cards and get one with a U.S. based billing address.   If you are abroad, you can likely get one from the U.S. embassy.