The Chicago Mart Plaza is the west extension of the Merchandise Mart:
350 N Orleans St, Chicago, IL 60654. The entrance is on West Mart Center Dr.
Parking is just $5/day for daytime parking (get ticket stamped at reception), and $25 for overnight.

Whether you're driving, walking or getting the 'L', please print out this PDF to help you get to the confernce easily, and also see the details below.

Driving and Parking
Approach from the South (you may have to loop around the Mart), cross over the Orleans/Franklin Bridge and take the first left onto West Mart Center Drive.
The building is marked 'West Mart Center'.
Drive past the taxi rank and past the entrance to the building and take a left at the end to enter the parking lot ($5/day for attendees!).
GoogleMap and driving directions here

Public Transportation
If you take the '"L", the Brown and Purple lines will drop you directly at the "Merchandise Mart" stop, leaving you on the second floor of the Merchandise Mart. Just walk through the building (direction of Jumba Juice) the far West side. You will then cross through a pedestrian bridge over Orleans Street and go around a corner to the elevators, take these to the 14th floor.

Taxis will cost approx. $40 from O'Hare and will need 40-50 minutes in normal traffic, 30 minutes more in rush hour. Taxis from Midway Airport are slightly less and travel times 10 minutes shorter.

Construction Warning:
Beginning on April 1st, the major interstate system surrounding Chicago will undergo a massive reconstruction effort. Several areas will have restrictions and lane closures, causing an alternate route to be needed for traveling into the city. Even those who are familiar with driving in and around Chicago should take a look at the Illinois Department of Transportation website before making travel plans. The following website provides up to date travel information and current progress on the project, so check back frequently as the date of the conference approaches:
Dan Ryan Expressway Reconstruction Project