well first off gender doesnt matter for the games and 2 you have to have Pokemon GOLD 3 if you don't u have to use gameshark(for gameboy) or the action replay(ds)
There are two ways:
A: Action replay and catch one
B: Nintendo Event and get a mystic ticket. Head to Navel Rock and catch it there (only for Pokemon Emerald, Firered, Leafgreen).
This is the ONLY LEGIT WAY! There is a game for the gamecube called Pokemon colosseum in this game you travel the world to save shadow Pokemon by purifying them, once you get level 100's in this game...