For everyone that thinks that you use a smokeball to evolve Eevee into Umbreon, that's not how you evolve Eevee. If you want an Umbreon, you have to use friendship points. Friendship points are invisable points that evolve Pokemon. To get friendship points to evolve your Eevee into an Umbreon, not an Espeon, you need to (if you want to do it the easy way) go to the underground stores in Goldenrod at night. Then have you Eevee groomed at night allot. The more you do it, the better. After you think you've done it enough, which is allot, have your Eevee grow one level at night. If it has enough friendship points (or happiness points) it will evolve into Umbreon. To get Espeon, do everything in the morning or day.
Warning: Friendship points lower if a Pokemon faints, is given something that you are
warned it will make you're Pokemon unhappy, or trade it. Things that boost it's happiness
are, grooming it, keeping it in your party, battling with it, and giving it vitamins.
(calcium, iron...) Things that do not affect it are, storing it in your pc, giving it
other items, cloning it, or talking to your gameboy (lol!).
As for getting to the Smokeball, (which helps you run away in battles) I don't remember.
I hope I helped and good luck! :D
i gave them to eevee at night (also works to get an espeon just do it at morning)