You would need to go to the McLean County, County Clerks Office at 115 E. Washington St. in Bloomington, IL. It would be best if you go into the office. They have card catalogs of birth, death, and marriage certificates that they do have on file. If it isn't in the catalogs, then there isn't a certificate. It is best if you look first before you request, because they will not refund money for any certificates that aren't there.
Births are from 1860 - 1940, deaths are from 1878 - 1973 and marriages are from 1831 - 1997. The researcher is only in on Monday, Wednesday, and Thursday mornings. I usually just fill out their form and drop it off with payment and a copy of my drivers license. They are really good at getting back to you right away.