Books published during the historical time period you are researching are primary sources. Search Google Books for digitized copies:
American History by Era: The Colonial Period, 1607-1750
American Decades: Primary Sources
Daily Life of African Americans in Primary Documents [2 Volumes]
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Suggestion: Click on Book Index (near top of the book's homepage) and, from there, click on link(s) to desired article(s).
American Civil War: Interpreting Conflict Through Primary Documents [2 Volumes]
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Suggestion: Click on Book Index (near top of the book's homepage) and, from there, click on link(s) to desired article(s).
Annals of America
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Combining search words for your topic PLUS any of the the search words below:

This was found using a search for "slave narratives"
U.S. History in Context is a great database to find primary sources. You can limit to primary sources or search for just a specific kind of source. Use the information and the images in the example search below to guide you in your search.
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Notice once you've limited to primary sources and see the results, there is a way to further narrow, or at least look to see what types of sources are included in the results such as government document, speech, editorial, excerpt, interview...etc.
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Each guidebook provides suggestions for primary sources for different events in history.
Term Paper Resource Guide to African American History
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Term Paper Resource Guide to Latino History
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Term Paper Resource Guide to Colonial American History
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Term Paper Resource Guide to Nineteenth-Century U. S. History
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Term Paper Resource Guide to Nineteenth-Century World History
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Term Paper Resource Guide to Twentieth-Century United States History
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Term Paper Resource Guide to Twentieth-Century World History
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