If you are in Kanto, travel to Lavender Town. He is two buildings south of the Pokémon Center. In Pokémon HeartGold and Pokémon SoulSilver, he is in a gold and purple tent. If you are in Johto, travel to Goldenrod City. He is in the building west of the gym. In Pokémon HeartGold and Pokémon SoulSilver, he is in a gold and purple tent across main street from the gym. If you are in Hoenn, travel to Slateport City. He is located in the house with the purple roof the the left of the Pokémon Center. If you are in Sinnoh, travel to Eterna City. He is located on the first floor of the building right next to the Poke Mart. If you are in Unova, travel to Castelia City. He is located on the 1st floor in the 3rd building from the gate to Route Four. If you are in Orre, travel to Agate Village. He is in the Day Care building by the waterfall. If you are in Kalos, travel to Camphrier Town. He is in the Pokémon Center, on the right-hand side. If you are in Alola, travel to Heahea City. He is in the Alola Tourist Bureau building.