Government Documents and Anthropology
There are many historic publications by various government agencies that contain rich ethnographic material. You will need to consult the older issues of the Monthly Catalog on paper to find these. Some of these historic publications will be indexes, like the 1954 publication of the Index to Schoolcraft's "Indian Tribes of the United States," (Gov Doc I 20.2:3:In 2/Index) which itself indexes a major ethnographic work dating from one hundred years earlier. Some publications are from agencies you might not expect to be interested in anthropology, like the Department of the Interior and the Library of Congress. Others are from quasi-governmental agencies like the Smithsonian Institution, publisher of, among many other things, the List of Publications of the Bureau of American Ethnology with Index to Authors and Titles.
Indexes to Government Documents
Many United States Government Documents are not listed in the library catalog. There are several ways to search for government documents, but those described here will be the most direct. You might also want to take a look at the library's Guide to Understanding the Government Document Numbering System before you head to the Documents shelves on the second floor. Many sources for government information are on the Web; be sure to look at the library's Government Documents page.