There are currently seven evolution stones in PokeOne. The common Fire Stone, Leaf Stone, Thunder Stone, and Water Stone can be found on the 4th floor of the department stores in Celadon City and Goldenrod City.
The Dawn Stone can be found on the Upper Mountainside of Mt. Silver on the left side in a pokeball.
The Dawn stone is used to evolve a Male Kirlia into Gallade and Snorunt into Froslass.
The Dusk Stone can be found in the Cerulean Cave to the left of Mewtwo by interacting with one of the green crystals Click Here for a map of Cerulean Cave.
The Dusk stone is used to evolve Murkrow into Honchkrow and Misdreavus into Mismagius.
The Shiny Stone can be found in the National park in the Johto region. Keep heading straight up and it should be behind the railing.
The Shiny Stone is used to evolve Togetic into Togekiss and Roselia into Roserade.