Exchange Service get all rooms list and get appointment each room

Hi,
I am into retrieving the list of all rooms within an organization. The basic purpose is to find all the rooms in an organization and find their respective appointments within the specific period of time. I can see the All Rooms using the image above (using the Outlook GUI)(from link)
http://tempuri.org/tempuri.html

But, how can I get all the rooms using the Exchanged Service Managed API.

Please help me..