in pewter city (i think, its definitely in kanto) there is an old man. talk to him and I cant remember if you have to answer a question but he will tell you about the olden days then give you a silver wing. hope that help :)
To the right of the town, there is a small hill will an old man standing on it. Talk to him and he will give to the Rainbow wing for Soulsilver, or the Silver wing for Heartgold.
in the radio tower
you dont use it it only unlocks a cave
you cant unless you trade from heartgold
it is an item used to summon lugia
you get the wing of the hoho in soulsilver and the wing of lugia in heartgold
Any time you want.
Yes you do.
If you're using heartgold, after beating the Pokemon league go to pewter city and an old man on a hill will give you the rainbow wing in soulsilver and the silver wing in heartgold.
you have to beat team rocket then the director gives you the rainbow wing
go to pewter city, then there is a man you get the silver wing
you talk to a man in pewter