Where and when can you find Suicune Entei and Raiku in this game and battle..

Both will run around Kanto after you obtain the National Pok�dex, depending on whom you started with. Starting with Bulbasaur yields Entei, Charmander yields Suicune, and Squirtle yields Raikou.

It depends what Starter you got.
Entai= Bulbasaur
Raiku= Squirtle
Suicune= Charmander

You can't find all three in the same game. It depends on the pokemon you start with.
Start with: For:
Bulbasaur Entei
Charmander Suicune
Squirtle Raikou

You can only see the legendary dog depending on which pokemon you chose as a Starter.
Squirtle=Raikou
Bulbasaur=Entei
Charmander=Suicune
They only appear at the wild after you beat the Elite Four.

You can't find them and battle them because you have to Trade them from Colloseum.

If you chose Charmander as the Starter you can find Suicune in the Kanto mainlands. If you chose squirle you will find raiko. If you chose Bulbasaur then you will fine Entei.

If you chose Squirtle you find Raikou in the wild running around in Kanto.
Charmander = Suicune
Bulbasaur = Entei
They roam around in Kanto after you beat the most powerful type of E4.

It Depends on what your Starter Was
Squirtle==>Raikou
Charmander==>Suicune
Bulbasaur==>Entei
They Can Be Found Anywhere After Getting The NationalDex