Ya just don't.
vulpix,growlite and evee
migrate or trade in fire red
u can find it on routes 36,37 and 48
You'll need to trade from Pokemon HeartGold, Diamond, Pearl, or Platinum.
It depends on the weather and the place.Sometimes you can get it near a very good weather.But usually no.
beat the gym leader
It says on the Pokemon Battle Frontier Drew cried, but he didn't in Pokemon Advance episode 454 as per the link in the related links section.
at a gamestop store
yes entei that is just a leg but if you are talking about Pokemon than yes rapidash growlite and many more there near mt silver
By Pokemon rangers or cheating
No, you cannot catch a mew in Pokemon Platinum without cheating.
stop cheating