- Illinois State Archives
Online databases provided by the Illinois office of the Secretary of State. Includes a database of Illinois Veterans, a statewide marriage index from 1763-1900, a death index 1916 to 1950, and more.
- Illinois Digital Archives
"Designed to be a searchable repository for the Illinois State Library's digital collections as well as those of other libraries and cultural institutions in Illinois."
- Digital Illinois
"A consortium of libraries in Illinois. It contains digital collections from libraries, historical societies, museums, and other cultural institutions in Illinois"
- Digital Past "Digital Past is a digitization initiative undertaken by libraries, historical societies, museums, and other cultural venues throughout Illinois in partnership with the North Suburban Library System (NSLS) in Wheeling, Illinois."
- Illinois Harvest
Digital resources from the University of Illinois at Urbana Champaign
- Cook County Genealogy
Database of marriages, births and deaths for Cook County, Illinois (Chicago)
- Chicago Historical Homicide Project
Database at Northwestern Univeristy containing Chicago Police Department homicide record index (1870-1930)