As of 10am 7/6/06, these are the hotels with rooms available:
 
per DCI's housing page:
Baymont Inn   8102 Excelsior Dr   $109
Comfort Inn   5025 CTH V DeForest   $99
Holiday Inn   1109 Fourier Dr.   $139
Marriot West   1313 John Q Hammons Dr   $124
Regent-A University House Community   1402 Regent St. E   $109
Roadstar Inn   6900 Seybold Rd   $89
 
per hotels.com (800-246-8357):
Americas Best Value Inn   3438 Hwy 12-18   $167
Super 8 - Columbus   $80
Super 8 - Beaver Dam   $66
Super 8 - Windsor   $72
Rodeway Inn - Lake Mills   $86
 
per travelocity.com:
Holiday Inn Express - DeForest   $103.56
...and other flea-bite motels way out of Madison...
 
per HotelsbyCity.com:
Hilton Madison Monona Terrace   $179
Country Inn Suites   400 River Trail Monona   $?
Country Inn Suites   904 E. Main Waunakee   $?
 
per orbits.com:
Residence Inn   4862 Hayes Rd   $179
Howard Johnson   3841 E. Washington   $109
Super 8 - Sun Prairie   $64
 
per expedia.com:
Sheraton   John Nolen Rd   $179
Hampton Inn   4820 Hayes Rd   $149
Fairfield Inn   8212 Greenway Blvd   $129
 
You may find that if you call direct to the above hotels, they'll say they're sold out... online booking works

research provided by Tony Riley