There are many books in the library to help you understand the process of conducting oral histories; we've highlighted a few below. You can find additional titles in the library catalog by clicking these subject headings:
This database includes books, reference works and journal articles from across the social sciences.
The resources cover every aspect of research skills training and can help researchers at all levels through every step of the research process.
I recommend starting at the Methods Map page and typing "oral history" (without quotes) in the search box; after making your selection, click the blue "search all content" link to find relevant materials.