you cant. well i think ive had it for ages and ive never had one.
You can not catch any of them in black or white, but I think that you can catch all 3 in diamond.
lucky for you if you go to the first route and talk to the girl there will be a pop up saying 'SHADOW POKEMON CATCH WITH ANY POKEBALL!' and that's a free shadow Pokemon!
you have to get it on any GBA Pokemon games
You can't catch a Butterfree on any game.
There is no such Pokemon as "Shadow" mewtwo. There is a regular mewtwo that you can catch like any other Pokemon. It's located in the Cerulean Caves.
magikarp
catch them (read the instruction booklet)
You can't catch anyone's Pokemon in any one of the Pokemon games made. The onlyway is to catch them on your own or to use cheats.
You can use a masterball or you can just catch them the normal way
You can't catch Lucario in any game before Diamond/Pearl.
yes. its master ball cheat
Any Pokemon can, its really just luck if you catch one that does. Hope this helps!!