needed to prove relationships. One of my favorite sites is the Cook County Clerk http://www.cookcountygenealogy.com. For more information about them and their collection click here. Keep in mind that in the state of Illinois, it wasn't mandatory to record births or deaths with the County Clerk until January 1, 1916. Also, the Great Chicago Fire in 1871 destroyed all Cook County vital records prior to that date. So don't get too frustrated if you can't find information around those times.
If you can't find the record you are searching for, but know the name and date, you can submit a request for someone to manually search the records. I have resorted to that with much success. The link to print their request form is here.
Once you've created a log-in account, you can do a quick and simple name search for birth, death, and marriage certificates. The one difficulty I've found with searching their site is spelling. You need to know exactly how the last name was spelled on the record or you won't find it. That can be difficult if for example you are looking for Polish names that are frequently misspelled. If you don't have any results with the actual name, try a soundex search. To learn how click here. Most records are available immediately for download. The price is $15.
- Birth certificates must be 75 years or older (before today's date in 1938);
- Marriage certificates must be 50 years or older (before today's date in 1963);
- Death certificates must be 20 years or older (before today's date in 1993).