To get Pichu, get Pikachu male and Pikachu female (or Pikachu male or female and Ditto). Bring them to the daycare woman on island four. Go out for a walk and come back later. Talk to the man outside and he'll give you an egg. Make him hatch and you'll get PICHU!!!
For Tyrogue, get Hitmonlee or Hitmonchan and bring him to the daycare woman with ditto. Then you know the routine. get the egg and make him hatch. You'll get TYROGUE!!!
PS: Breeding two Pikachus will make an egg faster than breeding a Pikachu with a Ditto.
PSS: Pichu will know thunder and Tyrogue will know a BUNCH of cool moves.