Ok - having presented this topic and answered a myraid of questions on this topic let me expound on this train of thought.
Native American - Used to refer to the original inhabitants of the "new World" after it became known as America named after Amerigo Vespucci, (another portugese fellow). Today refers to anyone born in the country since its naming.
American Indian - the term currently in use by the Federal Government in all of its dealings with Indian people. Google American Indian Liasion office.
Native American Indian - a combination of the first two terms to describe the original inhabitants of the current (primarily North America) American continents.
North American Aborigine - coined by modern anthropologists to describe the original peoples of nort america.
First Nations - term used in Canada to describe the original inhabitants of their lands.
You may hear all of these terms plus, Indin, NDN or hey you!
Tribal names work if you know for sure who you are talking too, as for me Ben works just fine just don't call me late for dinner!