The IRRC's oral history collection includes numerous projects (e.g., Arrowhead Civilian Conservation Corps Documentation Project), as well as hundreds more individual interviews. The online resources are of various types: (1) a master inventory of projects, as well as additional non-project interviews, sorted alphabetically; (2) a finding aid that is project specific; (3) select interview transcripts.
A finding aid is an inventory that lists the contents of an archival collection. It includes an overview explaining what each collection is, who created it, when, and what materials or topics are included. It may also include a detailed description listing the collections' contents, box by box. A finding aid will not list every item, but it will help you discover parts you may explore further by visiting the IRRC Library.