I'm not exactly sure,but I've heard you get him in south pallet town
How To Catch Bulbasaur In Pokemon Leaf Green?
You can't
You can't find Bulsar unless you trade with someone in leaf green or firered.You only can catch him if you use gameshark.
You cannot catch a Bulbasaur in the Official Pokemon Leaf Green ( that has not been modified).
Run and grab it
You get at the start.
You can only have bulbasur as a starter. I don't know about this but there might be a action replay for game boy