The accomodation deadline passed on June 30th. Hence, the Hyatt Regency has released the rooms that were held aside for the ACA participants. Thus, anyone still needing to reserve a room will be competing with the general public. The Hyatt is fully booked for the nights of July 18th and 19th. However, it is still worth a call there to check for cancellations. You MUST ask for the ACA conference rate, which is still applicable.
As a alternative, rooms are available (except for July 18th) at the neighboring Drury Inn Union Station (tel: 314-231-3900/800-325-8300) and the Hampton Inn Station (tel: 314-241-3200) at the same ACA conference rate ($96.00 + tax) which you MUST ask for explicity.
Other downtown hotels that you could try (at which there is no special ACA rate) include:
Courtyard by Marriott: 314-241-9111/800-321-2211
Drury Inn Convention Ctr: 314-231-8100
Holiday Inn Riverfront: 314-621-8200/800-925-1395
Holiday Inn Select: 314-421-4000/800-289-8338
Ramada Inn at the Arch: 314-621-7900/800-272-6232
Adam's Mark: 314-241-7400/800-444-2326
Crowne Plaza Majestic: 314-436-2355/800-451-2355
Embassy Suites Hotel: 314-241-4200
Mayfair Grand Heritage Hotel: 314-421-2500/800-757-8483
Regal Riverfront Hotel: 314-241-9500/800-325-7353
St. Louis Marriott Pavillion: 314-421-1776/800-228-9290
There are also a few student residence hall rooms available on the campus of the University of Missouri-St. Louis. These have been open only to verifyable students, but will now be made available to all for the nights of 17th-20th of July.