You can buy evolution stones in Black City and find them in White Forest, but you can only buy the items if specific trainers are there, and this applies to White Forest too ( no purchasing though). You can also apparently find them in "dustclouds", I'm not sure how this mechanics works.
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PART ONE:
Dawn Stone:
Route 10,
Wellspring Cave (Dustcloud),
Chargestone Cave (Dustcloud),
Mistralton Cave (Dustcloud),
Twist Mountain (Dustcloud),
Challenger's Cave (Dustcloud),
Victory Road (Dustcloud),
Giant Chasm (Dustcloud),
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Dusk Stone:
Route 10,
Mistralton Cave,
Wellspring Cave (Dustcloud),
Chargestone Cave (Dustcloud),
Mistralton Cave (Dustcloud),
Twist Mountain (Dustcloud),
Challenger's Cave (Dustcloud),
Victory Road (Dustcloud),
Giant Chasm (Dustcloud)
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Fire Stone:
Castelia City (Answer Pansear),
Desert Resort,
Wellspring Cave (Dustcloud),
Chargestone Cave (Dustcloud),
Mistralton Cave (Dustcloud),
Twist Mountain (Dustcloud),
Challenger's Cave (Dustcloud),
Victory Road (Dustcloud),
Giant Chasm (Dustcloud)
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Leaf Stone:
Route 6 (Show all forms of Deerling in Season Institute),
Castelia City (Answer Pansage),
Wellspring Cave (Dustcloud),
Chargestone Cave (Dustcloud),
Mistralton Cave (Dustcloud),
Twist Mountain (Dustcloud),
Challenger's Cave (Dustcloud),
Victory Road (Dustcloud),
Giant Chasm (Dustcloud)
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Moon Stone:
Pinwheel Forest (From Lenora),
Twist Mountain,
Wellspring Cave (Dustcloud),
Chargestone Cave (Dustcloud),
Mistralton Cave (Dustcloud),
Twist Mountain (Dustcloud),
Challenger's Cave (Dustcloud),
Victory Road (Dustcloud),
Giant Chasm (Dustcloud)
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Shiny Stone:
Route 6,
Dragonspiral Tower,
Wellspring Cave (Dustcloud),
Chargestone Cave (Dustcloud),
Mistralton Cave (Dustcloud),
Twist Mountain (Dustcloud),
Challenger's Cave (Dustcloud),
Victory Road (Dustcloud),
Giant Chasm (Dustcloud)
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Sun Stone:
Relic Castle,
Nimbasa City
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PART TWO:
FireStone Causes Vulpix to evolve into Ninetales.
Causes Growlithe to evolve into Arcanine.
Causes Eevee to evolve into Flareon.
Causes Pansear to evolve into Simisear.
WaterStone Causes Poliwhirl to evolve into Poliwrath.
Causes Shellder to evolve into Cloyster.
Causes Staryu to evolve into Starmie.
Causes Eevee to evolve into Vaporeon.
Causes Lombre to evolve into Ludicolo.
Causes Panpour to evolve into Simipour.
ThunderStone Causes Pikachu to evolve into Raichu.
Causes Eevee to evolve into Jolteon.
Causes Eelektrik to evolve into Eelektross.
LeafStone Causes Gloom to evolve into Vileplume.
Causes Weepinbell to evolve into Victreebel.
Causes Exeggcute to evolve into Exeggutor.
Causes Nuzleaf to evolve into Shiftry.
Causes Pansage to evolve into Simisage.
MoonStone Causes Nidorina to evolve into Nidoqueen.
Causes Nidorino to evolve into Nidoking.
Causes Clefairy to evolve into Clefable.
Causes Jigglypuff to evolve into Wigglytuff.
Causes Skitty to evolve into Delcatty.
Causes Munna to evolve into Musharna.
SunStone Causes Gloom to evolve into Bellossom.
Causes Sunkern to evolve into Sunflora.
Causes Cottonee to evolve into Whimsicott.
Causes Petilil to evolve into Lilligant.
ShinyStone Causes Togetic to evolve into Togekiss.
Causes Roselia to evolve into Roserade.
Causes Minccino to evolve into Cinccino.
DuskStone Causes Murkrow to evolve into Honchkrow.
Causes Misdreavus to evolve into Mismagius.
Causes Lampent to evolve into Chandelure.
DawnStone Causes male Kirlia to evolve into Gallade.
Causes female Snorunt to evolve into Froslass.
Everstone If held, prevents a Pokémon from evolving. From Generation IV onwards, it fails to prevent Kadabra from evolving.