Calendar- AutoAccept Appointments

You have a couple options:
1- Personally I like the use of scripts. You can go to:
www.exchangecode.com and look at the excellent autoaccept code that has been written.
Also check out www.slipstick.com for more information.
2- On a dedicated system log into and use Outlook 98 or 2000 to log onto the shared calendar mailbox. Under Tools>Options>Preferences|Calendar Options. Click on the resource scheduleing button. Select the automatic acceptence options you want. Leave Outlook open to allow automatic processing of the meeting requests.
3- Direct Booking. If all of your client use Outlook 2000 you can do direct booking. The Outlook client actually creates the appointment directly in the shared calendar, BUT only if the meeting scheduler puts the shared calendar into the Resource field. If the meeting is placed in the Required or Optional meeting attendee, then Option 2 must be used for the meeting to get accepted.
Also look at these two TechNet article on setting up Conference Room.
http://www.microsoft.com/technet/exchange/cfsetup.asp
http://www.microsoft.com/technet/exchange/cfbook.asp
(Please remove any spaces added to the above links)