Pokemon how to catch legendaries in diamond?

You catch giratina on top of mt. cornet in platinum, but catch palkia/dialga first. They are in the4 blue/ pink portals. Catch Azelf/Mesprit in the island caves on their lakes, and find Uxie with the pokeApp Map. Shaymin can be obtained with Oak's Letter Nintendo event, or with the cheat walk through walls. Just go up to the smooth stone and walk through it. keep walking and you will reach shaymin's Island. Arceus is only caught with the azure Flute on top of mt. cortnet, witch can only be obtained with the Nintendo event.