The room booking interface in Outlook is probably hidden or minimized.
Show
Create a new appointment in Outlook.
In the new meeting window, click Show Assistant on the eTASK tab.
Maximize
Create a new meeting in Outlook.
In the new meeting window, click on "Expand eTASK
Outlook Room Booking"eTASK Outlook room booking interface showing Show Wizard button, resource list with meeting rooms, and appointment scheduling form with date/time fields