Primary sources are first-hand accounts, that serve as original evidence documenting a period, event, people, idea or work.
Primary sources can be printed materials like books or newspapers, manuscript and archival materials like diaries and documents, artifacts, and audio/visual materials. Primary materials can be found in analog, digitized, and born-digital forms.
Some examples of primary sources include:
Be sure to evaluate the sites you find, particularly who created the site in order to determine biases and what information might be included/excluded.
Some libraries catalog their digitized archival collections in Williams​ WorldCat.
Note: some items will not be freely available or may just be collection finding aids.