Most Garage sales are a combination of Thursday, Friday, Saturday and Sundays. Garage sales on Thursday-Saturday are more prevalent in the suburbs. Garage sales Saturday and Sundays are more prevalent in the city. Check your local newspaper or community journal for a listing of local garage sales. Be on the lookout for neighborhood/subdivision wide garage sales.
Winnetka Congregational Church Rummage Sale has been going on for 80 consecutive years. This is by far one of the largest sales in Northern Illinois. The main sale is the second Thursday in May. In the fall, there is a slightly sale on the third Saturday in October. Check them out at WCCRUMMAGE.COM
The North Shore Chicago Rummage is a coalition of churches, synagogues and not-profit groups who have compiled an awesome list of some of the best rummage sales in the Chicago land Northern suburbs. Check them out at NorthShoreChicagoRummage.org