hes at the route were you first meet misty after you chase him around.
you have to get it from Pokemon platinum or diamond
jhoto and kanto regien Pokemon
You can't catch giratina in soul silver, you can only catch him in diamond, pearl, or platinum.
you get it in cian iwood from a guy
There Isn't
you dont make poffins in soul sliver
in the radio tower
You cant catch one, but you can get one by a WiFi event or traded by a friend. BTW the event has already Finished.
read the wall and catch all the unknowns
no
goldenrod
no you cant but you can catch mewtwo in a cave in cerulean