There are a LOT of primary sources online for early modern research topics. The websites below are good places to start, but you will discover other websites as you research.
Records from more than 35,000 individual slaving expeditions between 1514 and 1866 from archives and libraries throughout the Atlantic world, providing information about vessels, enslaved peoples, slave traders and owners, and trading routes.
Rich website linking to primary sources for all periods of European history. Organized first by country, and then loosely chronologically. Includes transcriptions, facsimiles, and, sometimes, translations. Maintained at Brigham Young University.
A website with links to primary source documents, most in English translation. Particularly useful for an understanding of the early modern economic conditions beyond Britain. Compiled by Paul Halsall at Fordham University.
"Early Modern Resources is a research portal for the early modern period (c.1500-1800 CE). It only lists websites that are free to access and focuses on high-quality resources that are suitable for advanced research, study and teaching."
"London Lives makes available, in a fully digitised and searchable form, a wide range of primary sources about eighteenth-century London, with a particular focus on plebeian Londoners. This resource includes over 240,000 manuscript and printed pages from eight London archives and is supplemented by fifteen datasets created by other projects. It provides access to historical records containing over 3.35 million name instances. Facilities are provided to allow users to link together records relating to the same individual, and to compile biographies of the best documented individuals."
Read the full text of Shakespeare's plays, sonnets, and poems for free from the Folger Shakespeare Library. You can also learn more about Shakespeare’s language, life, and the world he knew.
