You get it from Billy's Grandfather on route 25 after showing him some pokemon.
Chat with our AI personalities
At the Pokethlon Dome or at the Bug Catching Contest
After you battle and beat the gym
an evelution stone
No
Pikachu into Raichu, and Eevee into Jolteon. I don't recommend evolving Eevee into Jolteon. Espeon is way better.