It would be nice to know where you are starting from. If it is an address of a message sent to you click the star to the RIGHT of the address in the message header. This is not the star in the Star column of the mail page. If the star to the right of an address is not filled with color it is not in any of your address book. If the star is filled with color it is in one of your address books already. Clicking a colored filled star open the edit dialog box for that contact. If this is not what you are asking provide more details of what you are asking.