I’ve registered a “dot-com-dot-tw” before. It requires that you have a registered business in Tawian. You will will need to find the right registrar with these guys:
You can fill out the online forms with whoever you go with to register, but you will need the company number, and to finsih registration fax in you company license and pay through bank transfer. It cost me 2000NT for a two year registration when I did it.
After it is registered, you can point your domain to any IP address you want, including servers in the US.
I hear there are services out there that will “rent” you a “dot-com-dot-tw” address for a fee, meaning they are the actual registrant since they are a Taiwanese company, but they will do it for you. I don’t know who these services are.