Here is the link for MESA Summer School participants to register for on-campus housing:

http://www.housing.ucsb.edu/conferences/web_reg/mesa-housing-2012.htm

Students will be housed in Manzanita Village in a mix of single (8 rooms) and double rooms (18 rooms) and the package includes daily meals, starting with dinner on the night of arrival (Sunday August 12) and ending with breakfast on the day of departure (Saturday August 18).  For those willing to share a room, the cost (including meals) will be ~$540, whereas the 8 private rooms cost ~$670. An option is also available to arrive a day earlier, on Saturday August 11, in which case these prices go to approximately $625 and $780. Please see the registration link above for more precise information and travel information.

All of the lectures will be held at the Loma Pelona center, adjacent to the housing:

http://www.housing.ucsb.edu/conferences/meeting.html