The city with the cave paintings I think it's celesic town
You can buy timer balls at Canalave city and at the Pokemon League.
You can buy them at the Pokemon mart at the Pokemon league. I buy my timer balls, heal balls, etc. at the Pokemon mart in canalave city
buy them+
Timer balls can be found in the Pokemart in Rustboro City
You can get them in snowpoint city
Rustbourd city
You buy them in rustborro city
any
Once you help the Devon corp you can purchase timer balls and repeat balls at the rustboro city pokemart.
i think u have to import from Pokemon dp or platinum
Rustboro city
Timer balls are sold in the rustboro city pokemart.