Well, thanks to the folks here on this group I was able to write the
VBA code needed to add a meeting room to an open meeting. I thought I
would share the code here for others to use or improve upon.

This code would be attached to a form with;
1) listbox (lbxRooms)
2) button (cmdCancel)


I then created a macro attached to the meeting schedule window to load
and show the form when activated.


regards,
DP
==============code=================

Option Explicit
Dim strCity As String 'city code used in address name
Dim strRooms As String 'address entries
Dim Meeting 'current meeting
Dim myRecipient 'the room I finally pick
Dim UseThisRoom 'the room I finally pick
Dim myAddressList As AddressList 'address list
Dim AddressEntry As AddressEntry 'addressentry


Private Sub UserForm_Initialize()
Call GetRooms
End Sub


Sub GetRooms()

'use the global address book, incase another is default
Set myAddressList = Application.Session.AddressLists("Global Address
List")

' go through address book and get each meeting room
For Each AddressEntry In myAddressList.AddressEntries

strRooms = AddressEntry.Name

'look only at mtgrm entries (all room anmes begin with mtgrm)
If Left(strRooms, 5) = "mtgrm" Then
'look for the available rooms
Call GetFreeBusyInfo
End If

Next
End Sub


Sub GetFreeBusyInfo()

Dim myFBInfo As String 'getfreebusy information for the meeting date
Dim MyStart 'meeting start tiem and date
Dim MyDur 'number of minutes in length the meeting is
Dim MyStartTime 'number of minutes after midnight meeting starts

'use the active meeting as reference
Set Meeting = Outlook.ActiveInspector.CurrentItem

MyStart = Meeting.Start 'get the meeting start from active meeting
MyDur = Meeting.Duration - 1 'get dureation from active meeting

'get number of minutes between midnight and MyStart
MyStartTime = DateDiff("n", (Format(MyStart, "Short Date") & "
12:00:00 AM"), MyStart)


On Error GoTo ErrorHandler 'ignore rooms that where freebusy is not
available

'get the freebusy time for the meetign date
myFBInfo = AddressEntry.GetFreeBusy(MyStart, 1)

'see if time is available (all minutes within meeting duration are
0)
If Mid(myFBInfo, MyStartTime, MyDur) = 0 Then
'if available add it to the listbox
lbxRooms.AddItem AddressEntry.Name
End If

ErrorHandler:

End Sub

Private Sub lbxRooms_DblClick(ByVal Cancel As MSForms.ReturnBoolean)

'use the room that is double clicked on
UseThisRoom = lbxRooms.Value

'add the selected room to current object as a resource
Set Meeting = Outlook.ActiveInspector.CurrentItem
Set myRecipient = Meeting.Recipients.Add(UseThisRoom)
myRecipient.Type = olResource

'unload form after room is added, since only one room is ever needed
Unload Me
End Sub


Private Sub cmdCancel_Click()
'cancel and close the form without adding a room
Unload Me
End Sub