pal park
the guy from the team galactic gives you one to catch girantina in the distortion world
bad code
There is a socialite who only has a Roselia.
go to iron island. riley gives it to you at the entrance
in Platinum on your way to the spear tower the detective gives it to you in Mt Coronet. it is most likely the same in pearl.
cyrus gives it to you
Cyrus gives u one
you can not get a master ball in Pokemon platinum only the one professor Rowan gives you
the guy from the team galactic gives you one to catch girantina in the distortion world
2 the one Cyrus gives you and the one you can win at the veilstone game corner
Cynthia's grandmother gives it to you.
someone gives it to you.
jortan
Cynthia gives it to you.
theres a guy who gives you 5 of them if you show him a certain pokemon. hes thenews reporter guy in solaceon town. they dont start selling them until after the 7th or 8th badge.
beside solemn town's Pokemon healing centre there's a house and when you go in it there's a fat man that gives you a assignment and when you complete it you get a heart scale and a few poke balls.
Get rid of some of the master balls! the number of master balls you have is the number of the pokemon