You mean this homepage here?
That's who I used (and still do use). I believe Delaware is the cheapest and simplest - which is no doubt why they are based there. I've also heard of people using Nevada for this kind of thing. Not sure what you get for the "international package", I remember that mine was cheaper than that but it was 7 years ago now. You only need something very simple, the corporation is never going to trade and has exactly one officer.
n5296s (which, you can easily establish, is actually owned by a Delaware corporation called Metavol Inc).