It's in celadon city right below the pokemon center and to the left.
Porygon
It Is In The Game Corner.
game corner
At the game corner in Celadon City.
I think you can get it the safari zone but you can get at the game corner
At the celadon city game corner a man behind the counter in the game corner will give you coins.
Defeat team rocket at the game corner and Pokemon tower.
Mt moon, Rocket game corner, the guy in the two island game corner gives you one as well, Pokemon mansion.
get 2800 coins for the game corner to trade you a dratini
The purpose of going into the game corner is so you can infiltrate the Team Rocket base in the basement.
You can get him at the game corner in celadon city for 9999 game corner coins but for less in leaf green... I don't know why though...
Route 24, Route 25, Game corner exchange.