You have to have Pokemon fire red for GBA. Catch it on that.Once you have beaten the elite four and finished the Sinnoh Dex (on diamond) the Pal Park will open and you can migrate it from fire red to diamond.
Trade
Ash has 6 Pokemon in Diamond version
u can't get a lvX Pokemon in diamond version
Growlith Issac Lim
By trade.
Trade
you cant.you have to insert Pokemon firered.
You can get growlith at route 201 and 202 if you have Pokemon firered insterted.
mostly: evee------flareon vulpix-----ninetails growlith---arcanine
u have to w8 for a migration to come or get an action replay then get the Pokemon modifier and pokedex cheats.
You could find wild Growlithes in Route 48.
You can catch a Growlith in the Pokemon Mansion on Cinnabar Island.
Ash has 6 Pokemon in Diamond version
I dont have pokemon diamond
Im afraid there is no other way except using an action replay cheat cartridge.
Fire Stone
u can't get a lvX Pokemon in diamond version