You climb the peak of Mt. Cornet to get to the Distortion World.
You go to the three caves and catch them.
catch palkia (pearl) catch dialga (diamond)
the legendary Pokemon in diamond and pearl are dialga and palkia.
No, a Bidoof cannot evolve into any Legendary Pokémon in Diamond.
Heatran
a lot of legendary Pokemon
Dialga
you cant unfourtanately
arceus
The 'Diamond statue' you speak of is located to the East of Enterna City. This statue is the same in Diamond and Pearl, as you can see it is a mix of Dialga (Diamond Legendary) and Plakia (Pearl legendary.) If this is not what you ment by your question, feel free to cantact me on my message board.
you can't catch it because you already beaten the legendary
Go to the team galatic base after battling the boss... P.S. I forgot the name