How do you catch Eevee in firered?

You can't catch Eevee in FireRed! Eevee is only available in the Johto region games (Gold, Silver, Crystal).

Here are some Pokemon you can catch in FireRed that evolve similarly to Eevee:

* Vulpix (Fire-type) evolves into Ninetales with a Fire Stone.

* Growlithe (Fire-type) evolves into Arcanine with a Fire Stone.

* Porygon (Normal-type) evolves into Porygon2 with a "Upgrade" item.

If you really want to catch an Eevee, you would need to play a Johto region game or use a trading method to get one into FireRed.