Delete User Notes

Does anyone know how to do a delete for user notes.  So far, I search for user notes that contain a certain title.  I bring in each result into an array of records.  The following code is the remainder.  It bombs out saying invalid typeid.  How do we find out what the typeid is?

  For i = 0 To response.totalRecords - 1
            Dim custNote As New Note
            custNote = records(i)

            Dim customRecordRef As New CustomRecordRef

            customRecordRef.typeId = custNote.GetType.ToString
            customRecordRef.internalId = custNote.internalId

            Dim delResponse As WriteResponse
            delResponse = Service.delete(customRecordRef)
next