Sorry, there's only a thunderstone in the mall. Talk to a man on the 3rd floor to get it.
You can buy one from the PokeMall.
Three places. One, if you go throughout all of Mt. Moon, I'm also sure you can find one while traveling the game, and I think you can buy them at the PokeMall.
go underground and keep digging till u find a water stone or a fire stone
The water stone is found in the Solaceon Ruins. Go into all the chambers with a rock in the middle of them. You will find a Water stone. Also, in the Solaceon ruins, you can also find a Thunder stone and a Fire stone.
You can find a Water Stone on Wednesdays in the Pokeathlon Athlete Shop for 2500 points.
You need a Eevee and a water stone use the water stone on eevee! Simples!
Water Stone...Well... If I remember correctly, there's a guy who's willing to trade a water stone for a Blue Shard. Oh! And you can find one on the Abandoned Ship.
If you are really lucky, you will be able to find one by digging underground. I've tried it, and only got a Leaf stone, a Sun Stone and a Moon Stone. Sigh. Do you want a Shield fossil? I've got 992 (apparently) and they're Pearl only! *wink wink*
Pokemon requiring a stone to evolve:Eevee - Thunder stone, Jolteon (you can't find this Pokemon in Ruby) Eevee- fire stone, Flareon (you can't find this Pokemon in Ruby)Eevee- water stone, Vaporeon (you can't find this Pokemon in Ruby)Sunkern- sun stone, Sunflora (you can't find this Pokemon in Ruby)Jigglypuff- moon stone, WigglytuffSkitty - moon stone, DelcattyNidorino- moon stone, Nidoking (you can't find this Pokemon in Ruby)Nidorina- moon stone, Nidoqueen (you can't find this Pokemon in Ruby)Growlithe- fire stone, Arcanine (you can't find this Pokemon in Ruby)Gloom- sun stone, BellosumGloom- leaf stone, VileplumeStaryu- water stone, StarmiePikachu- thunder stone, RaichuLombre- water stone, LudicoloNuzleaf- leaf stone, ShiftryVulpix- fire stone, NinetalesHappiny- oval stone Chansey
ON route 9. It is where you get Hyper beam and giga impact
Use Surf in Driftveil and surf right. The iitem on the rocks is a Water Stone
You can dig it up underground