Well in all honesty there are millions of people who have internet business in the U.S. who have not registered those businesses with local or federal tax agencies. There is not enough man power and to my knowledge it has not been regulated by the government so is it a requirement no, but some people do so that they are not caught up in trouble down the road.

Each state in the U.S. has it is own rules and laws governing businesses as well as each city which has laws for and requires registrations of home businesses.