Where can you find a thunder stone in soulsilver?
You buy it with points at the Pokeathlon Dome.
The easiest way to get a thunder stone is to earn 2500 points at the place by the national park the thunder stone will not be there everyday because everyday there's a different stone You could show a Pichu to Bill's Grandfather on Route 25, or you can buy it on Thursdays in the Pokeathlon Dome for 2500 points.
Come first in the Bug Catching contest and a Thunder Stone could be your prize. Get called to Route 38 and you could be given a Thunder Stone. Show Bills grandfather a Pichu on Route 25 and he'll give you a Thunder Stone. Use the Dowsing Machine on the Yellow Forest Route on the Pokewalker and there is a 5% chance you get a Thunder Stone after 6000 steps. Buy it at the Pokeathlon Dome…
All elemental stones are located in the underground, just keep digging anywhere there's a sparkle, and you should find one eventually. I personally found thunderstones the hardest to find. Woooooo! You can get a thunder stone on the blue thing in sunnyshore city to get a thunder stone go under round and dig in the wall and u will find som treshers sum tims it will be a stone