I use the same meeting location for most of my meetings and appointments in Outlook. Is there a way to set up a default location whenever I try to make an appointment/calendar event? 

goto Account settings and then data files

change the default data file to which you want and then outlook will save meetings there

The location field shows the 10 most recent locations. If you start typing the name it should come up, although that is not working here.

I don't think saving a custom field will work because the MRU list can change but you could use a macro to create a new appointment and set the location field.

BTW, this is all you need to create a new apt using a macro -

Sub createappt()

Dim olAppt As AppointmentItem
Set olAppt = Application.CreateItem(olAppointmentItem)

olAppt.Location = "My Favorite place"
 olAppt.Display
End Sub

you are awesome.