What pokemon will evolve when I use the leafstone and firestone and so..

Leafstone- Gloom into Vileplume, Weepinbell into Victreebell, Paras into Parasect, Exeggcute into Exeggutor

Firestone- Eevee into Flareon, Growlithe into Arcanine, Vulpix into Ninetales

Thunderstone- Pikachu into Raichu, Eevee into Jolteon, maybe others.

Water Stone- Eevee into Vaporeon, Staryu into Starmie, Poliwhirl into Poliwrath

Moon Stone- Nidorino/A into Nidoking/Queen, Jigglypuff into Wigglytuff, Clefairy into Clefable

For the fire stone: you can evolve, Growlithe to Arcanine, Eevee to Flareon, Vulpix to Ninetales

For the water stone: you can evolve, Poliwhirl to Poliwrath, Eevee to Vaperon.

For the leaf stone you can evolve: weepinbell to victreebel, gloom to vileplume

For the thunder stone you can evolve: Pikachu to Raichu, Eevee to Jolteon

For the moon stone you can evolve: jigglypuff to wigglytuff, clefairy to clefable, nidorina to nidoqueen, nidorino to nidoking,

I hope I have helped....

If you want the other stones you can buy them in Celadon City Department Store. I don't use them much though.
I only know that Vulpix evolves into Ninetails with a Firestone.
Ponyta evolves into Rapidash with a Firestone.
Poliwhirl evolves into Poliwrath with a Waterstone
Eevee evolves into Flareon with a Firestone.
Eevee evolves into Vaporeon with a Waterstone.
Eevee evolves into Jolteon with a Thunderstone.
Gloom evolvs into Vileplume with a Leafstone.

Growlithe evolves into arcanine with the fire stone

Firestone:growlithe into aricane,eevee into flareon,

Eevee + leaf stone = leafeon
Pikachu + thunder stone = raichu

Well if you are using Pokemon Yellow I am afraid to say that the internet says it is un obtainable in Pokemon Yellow so yes