There is not one, but you can attach it to a poke'mon from Fire Red or Leaf Green. Same with Fire stones. You can get unlimited stones from Fire Red and Leaf Green.
you cannot buy a water stone
you can use a water stone on lombre
abandoned ship
You use a WATER STONE on Lombre to get Ludicolo.
get a life. then get it at the abandoned ship!
You can't get Lucario in Ruby, Saphire or Emerald. Diamond, Pearl and Platinum only. sorry....
On the abandoned ship.
You can't in Ruby, Sapphire, or emerald, you have to look for them.
Evolve a lotad then use a water stone on lombre.
Lombre and etc
It evolves by use of a water stone, level has nothing to do with it.
all you need is a blue shard and go to the shard maniac just of mossdeep and he will give you a water stone and a water stone can evolve starmie, and lotad :)