Where do you get a metal coat in Pokemon Platinum?

there r 3 ways:

1.you can find it in Iron Island

2.when you arrive on Pokemon platinum after entering hall of fame,there is a house, which is Byron is there (Byron is not ALWAYS there), it is rare sight to see him there inside,before he gives the metal coat, he talk about his son,Roark,after that he will apologize & ta-dah he will give metal coat

and:

3.Wild Pokemon may be holding it ( wild Pokemon holding items: 5%)

Following:

MAgnemite

Magneton

Steelix

Beldum

Metang

Metagross

Bronzor

Bronzong

Magnezone

(Wild Pokemon Holding items & Pokemon info Got it from serebii.net & I DO NOT OWN serebii.net, it is just my favorite website :DD)

-PokeHelpThatsMe