Hours are 8am - 4pm and admission is $10. Early bird shopping begins at 7am and admission is $30. There are plenty of vendors to keep you busy for a few hours so it is possible to make a full morning or afternoon of it. Stalls line up and down Randolph and fill the parking lot and audiotorium of the Plumbers Hall building on West Washington.
Prices vary from vendor to vendor and month to month, but we will say there are items in all price ranges. We've brought home a few small treasures over the years (the markets began in 2004) but if you snag a big one, home delivery is available.
Here is a list of current vendors and features.
Good luck hunting!