Hi, karaflanagan.
1. Create an appointment on the calendar. Fill out the details, but don't add any attendees.
2. Click the Office button in the upper left of the appointment and select ave As.
3. When the dialog-box appears, make sure that "Save as type" is set to "iCalendar Format (*.ics)"
4. Save the file
5. Create a message and add the attendees as BCC addresses
6. Attach the iCalendar file saved in step #4
7. Send the message
The recipients will have to open the attachment and add the appointment to their calendar. You will not get any metting acceptance messages, so you'll have no way of knowign who accepted. If you need to know who accepted, or need this to appear as a normal meeting request, then you're out of luck. There's no way to do that using BCC.