Not sure where you get the idea of a 'contact person'. To register a .us, you must either live in the U.S., be a business in the U.S. or you must have a bona fide presence in the U.S. If you don't meet the requirements, you are ineligible for a .us domain. You are not aloud to register a .us domain if you don't qualify by using someone else's information. You can read the requirements here: neustar.us/the-ustld-nexus-requirements/