Is it just mainly American...?

No, actually the whole Creationism thing started in Australia, where Ken Hamm is from. He broke off from the group that started there and came to america to start Answers In Genesis (right here in ky) and it just grew from there. A lot of the people he got donations for the museum are from australia as well. Creation Ministries International is the name of the group he came from. Both Creation Ministries International and Answers in Genesis have offices in the UK. But they actually don't have a very large following... they just have very large mouths. => Offices are in US, UK, New Zealand, Australia, Canada and South Africa.