How do I get Shaymin in platinum?

Question

Shaymin 1:is cute 2: none!

Answer 1

You needed an item, Oak's Letter, but it was only available for a short period of time.

So the only way now is to trade, or use Action Replay to get the Pokemon or item.

Answer 2

It's in flower paradise
http://pokemondb.net/location/sinnoh-flower-paradise

Comments

HOW!
NOT WHERE!