The museum of Native Americans actually has two locations: one in Washington and one in New York. Both are part of the Smithsonian Institute and, like all Smithsonian museums, they have free admission. The New York collection is quite small and you can visit it fairly quickly. The building itself is interesting though and overlooks the small park in Bowling Green. I saw an interesting collection of clothing and tools from several ethnic groups (not only from the US, but all across the Americas). The colors were enchanting and I stopped to have a good look before continuing to the temporary exhibition about an Indian village in the Southwest.