at mulch iland
Hearthrome city
I guess you can't but qny
You can buy net balls at the mossdeep city pokemart.
You can get net balls at most pokémarts like the one in sunyshore city and the pokémon league net balls help you catch bug and water type pokémon -hoped i helped you- ~Ninjachoco~
my friend said to use lots of net balls and timer balls which you can get pokenemon leand and you have to have a nation pokedex
Once you get to go to the safari zone there will be a girl who will sell nest balls.
Go to Pastoria City and there will be two people at the counter. Press A in front of the guy on the left and he sells dusk balls, quick balls, and i think net balls.
Well if you go inside some poke'marts you can buy them from there. Hope this helped!!
Great Balls:fallabor town Net Balls:Mossdeep city.
Ranger net
Mossdeep City
Weaken it to red hp, paralyze it then use many net balls or ultra balls.