Stephenson County Birth, Death, & Marriage Certificates (non-certified copies) on microfilm
Births: 1878 – November 4, 1918
Marriages: 1837 – December 29, 1940
Deaths: 1878 – December 27, 1968
Delayed birth certificates: primarily the 1940s, with some earlier births included
Stephenson County (IL) Probate Index 1818-1950. It covers wills and guardianship records, also mental competency. It indicates the box number where the records can be found. These records may be viewed at the courthouse (Office of the Circuit Clerk) – 2nd Floor Stephenson Co. Courthouse (actual records housed on 3rd floor).
Federal census materials
Federal Census Microfilm 1820 – 1930 for Stephenson County and some adjacent counties.