I’m Swedish but I live in Thailand. While registering my account, I noticed that Thailand was not an option for the registration, so I picked Sweden. The problem is now when I try to register my credit card for the Playstation Store. As I only have Thai credit cards, the validation doesn’t work! And I can’t choose my Thai address as the billing address already is already set to Sweden.

Is there anyway I can change the billing address to Thailand?

BR /// Rob

I think you're stuck...if Thailand wasn't an option when registering, it must not have any support for Thailand (yet)

Traditionally Sony has spurned Thailand because of rampant piracy. Their stance was: We are just not selling our game systems there because we can't sell any games (which is where we make the money).

So chances that Thailand is going to be officially supported at some point are extremely slim.