Mary McCoy was born March 03, 1948 in Lancaster, New York. Her family moved to Las Vegas, Nevada on December 26, 1959. After graduating from Basic High School, McCoy immediately enrolled at Nevada Southern University, which was in the midst of growing into the University of Nevada, Las Vegas (UNLV). During the summer of 1967, she worked at the university's library moving books into the expanded facility. Though she altered her studies program from education to English, she continued to work at the library and continued the job after graduation.
In 1975, McCoy and her husband, Duncan, moved to Bloomington, Indiana, so that Duncan could pursue his graduate studies and take a Book Mobile librarian job. For the next fourteen years, the couple followed a variety of opportunities guided by Duncan's career. In 1989, they returned to Las Vegas. McCoy had agreed to the move—as long as it was to a city where she could find a college library position. She worked in UNLV Libraries for a total of 28 years in acquisitions, government documents, and Special Collections.