I've just landed here hoping to find an answer to my question.
I will be exhibiting at a miniature show that will take place next April at the Marriott O'Hare. Agreements with the show organizers have it that I must stay at the same hotel during the show and there's a special group rate for us, available until March 28. I tried to book a room (following a link provided by the organizers) there but, apparently, there are only single-occupancy rooms available. I'd like to contact directly the hotel about this but I can't find an email address for it (telephone calls are out of the question since I am living in Italy).