Where to get the water stone

Answer from: PokeInfo-er
When you travel from ecruteak city to mahogany town by using surf through route 42, there is a fisherman named tully, add him to your phone list and if he finds something he will call you. there are many chances of water stone....(i got one and evolved my poliwhirl to poliwrath and now taught him dynamic punch...............{actually 4 years ago}

i actually don't like dynamic punch that much for its iffy accuracy but its fit for poliwrath as it confuses for sure (100percent chance!)

Answer from: Apong
In kanto, go to cerulean cape above cerulean city. after beating the 6 trainers, go ahead. you will find a house. enter it and talk to the old man. he'll ask about a round green pokemon. show him oddish. you get a leaf stone. he'll ask about another pokemon shaped like a star. show him staryu. you have a water stone. you can get staryu while fishing at night in olivine city in johto.