To get the password to the king go the the Book icon on your V3 and then scroll to "point" and hit the "B button" (Secound button) and it will say "Donation to the king?" if you hit yes it will allow you to donate to the king with your own Gotchi points that you have earned.
Donate the following ammounts to go to the king and get a item:
Ring: 5001 gotchi points
Cape: 12001 gotchi points
Crown: 30000 gotchi points
Be sure to ensure you dont forget the password as you will not get it back unless starting a new Tamagotchi.