If your looking to play 18 on the North side of Chicago and keep it under $30, here you go. Twilight pricing starts at 2:30pm and is $29 with cart for 18. They have 27 holes here which is nice if you want to mix and match your front and back nines.
This course is 45 minutes from the evanston/skokie area unless your speed racer on a mission from above. In either case, this place is a decent choice for getting some good, cheap rounds in.