Taxis typically aren't hard to come by in Chicago. There are 7,000 of them within the metro area and they're readily hail-able from major thoroughfares. The "flag pull" fee is $2.25, then it's $.20 for each additional 1/9 of a mile. Wait time is $.20 for every 36 seconds.
Yellow Cab Chicago: 312-829-4222
Checker Taxi Chicago: 312- 243-2537
Chicago Carriage Cab: 312-791-1273