According to the Library of Congress, PRIMARY SOURCES "are the raw materials of history — original documents and objects which were created at the time under study. They are different from SECONDARY SOURCES, which are accounts or interpretations of events created by someone without firsthand experience." For example, an interview with James Dean while he was alive would be a PRIMARY SOURCE. A fictional movie starring James Dean as an actor or a book written about him after his death would be SECONDARY SOURCES.
Example Primary Sources include:
archives & manuscript material artifacts like clothing & furniture audio & video recordings diaries government publications & records journals, letters & diaries maps newspaper & magazine clippings oral histories photographs speeches & other original materials
Example Secondary Sources include: newspaper article summarizing a scientific study, review of a musical album or theater performance, biography about a famous person, etc.
PRIMARY RESOURCES TO CONSIDER as a starting point:
WHEATON NORTH DATABASES, especially Britannica, US History in Context, and World History in Context