You could just hit the Spacebar a couple of times to indent a line, but there's a better solution. When you want to edit the Note field of an item in NoteTaker, PhoneBook, DataBase, WorldTime or Appointment Book, highlight the item in the main screen and press (F3) (Note).
NoteTaker Full View Screen: Graphic
You go to a full screen view of the Note field. The Tab key will insert an indent in this view.
Rich Hall Editor, HP Palmtop Paper