Online Guide to Primary Sources
Created by UC San Diego Librarian, Kelly Smith, this online guide will help you find online primary sources
Internet History Sourcebooks Project
Huge collections of well-organized primary texts, including Internet East Asian History Sourcebook
Historical letters and accounts of the Silk Road in Chinese history; includes many significant Silk Road figures; and translated works
Primary sources can often be found (hyperlinked) in the bibliographies or footnotes of these scholarly e-books
You can also try a Google Scholar search with your topic keywords and the word "primary source" in quotations
Significant primary materials from countries and cultures around the world