catch him
Dialga is #483 in the national pokedex, and it is a Steel-Dragon type Pokemon.
Dialga is # 149 in the pearl pokedex
#483
Yes. The part of the story when you can catch Dialga and Palkia is not unlocked until you get the National Pokedex.
If you mean Gible, ( which i know is what you mean ) then he's #443.
in the national pokedex: arceas in the regular pokedex: dialga
Dialga cannot be encountered in Pokemon Pearl, but you can have it entered into your Pokedex. You'll need to go to Celestic Town and go into the big house and talk to the elderly lady. She'll talk about Dialga and show you a picture of Dialga in a book; this will be recorded into your Pokedex.
dialga is the best.
it is dialga
On the sinnoh pokedex it is Dialga; on the national pokedex it is Dragonite.
You can either trade with a friend or request a Dialga in the GTS. It is impossible to capture Dialga in Pokemon Pearl without the Action Replay, but you can get the Pokedex data for it from Cynthia's grandmother in Celestic Town. This Pokedex data would make it possible for you to get Dialga via GTS.
you need to get the national pokedex then go to mount coronet and they will be there