The Cycling Index of Northern Illinois Cycling lists lots of races -- https://nicyc.com/ And Silent Sports Magazine has a cycling calendar for the whole region (and highlights other sports too - great local resource) -- https://silentsportsmagazine.com/cycling/
I use Gravel cyclist dot com for my races. Recently though I came across a better way though. Go into bike reg which runs most of the races. Pick gravel and then put in your zip code and how many miles you are willing to travel. Works really well. Good luck
