No he is given to you at the start with the choice of 3 by that gay professor
You need to have selected Bulbasaur as your starter to get Entei wild in your game.
If you chose Bulbasaur or Charmander as your starter pokemon, then Raikou can't be found in the wild. If you chose Squirtle, however, Raikou can randomly be found in the wild (excluding Sevii Islands.)
You can't find Bulbasaur in the wild on Pokemon Diamond or Pearl (not sure about Platinum).
Choose it as a starter Pokemon. You can't find wild starters in any game. As an alternative, you can get a Bulbasaur in one game and trade it to your other game.
If youre not going to trade them from other games/people, then you can't. You chose bulbasaur, so you can't find the other two wild. Can still trade though. :)
You can find wild haunters in Pokemon tower and lost cave.
Entei can be found in Leaf Green if your first Pokemon was Bulbasaur and you've beaten the Elite Four. Entei can be anywhere in the wild. There is no exact location.
You cannot find Charmander in the wild in Pokemon LeafGreen. You will have to choose it as your starter Pokemon at the beginning of the game. If you chose another Pokemon, you will have to trade with someone to get it.You can get charmander only at the beginning of the game.
It is a starter pokemon. You can not find it in the wild. You can also trade for it.
you can find bulbasaurs in "Broags Garden Entrance" in the wild. It is connected to zone 30.
There is nowhere the player can capture a wild Bulbasaur in Pokemon Crystal. It can be traded using the Time Capsule.
If you have the starter Squirtle, you will find Rakio in the wild after beating the Pokemon League.