Ames Sheldon grew up in Wayzata, Minnesota. After graduating from Northrop Collegiate School, she attended Bryn Mawr College, where she majored in English. After graduating, she worked in the legal department of a multi-national chemical company, as a reporter at two newspapers, as office manager of a start-up auto salvage yard, and eventually as a grant writer and development officer for a variety of nonprofit organizations, ranging from the Sierra Club in San Francisco to the Minnesota Historical Society and the Minneapolis Public Library. She has an M.A. in American Studies.

Ames decided she wanted to be a writer at the age of nine. Many short stories and poems later, she worked as lead author and associate editor of the ground-breaking Women’s History Sources: A Guide to Archives and Manuscript Collections in the United States (Bowker, 1979), which contains descriptions of collections of original primary source materials pertaining to the history of tens of thousands of women and women's organizations from the colonial period through the 1970s. In the process of working on this monumental 1,100-page reference book, Ames discovered her love for women’s history and for using primary sources for research.