You can check Bill's Grandfather on Rt.25 in Kanto and if he wants a fire-type pokemon, he'll give you one. or you can go to the Pokeathelon in the National Park, sometimes they sell them there for points.
Fire stone
Fire Stone
Well..if there is a Pokemon that holds a fire stone...but i found mine in a cave
Fire stone
you can get the fire stone at the pokeathon dome (near the national park) as a prize on certain days
Fire Stone Water Stone Thunderstone Leaf Stone Dusk Stone Sun Stone Moon Stone Dawn Stone
you have to get a grolithe and bring it to bills house in kanto
Growlithe evolves when you give it a fire stone
you need the fire stone... i think you canget at the bug catching contest.
Growlithe evolves into Arcanine when you give the Pokemon a fire stone.
Ninetales isn't available in Heartgold. You have to trade one from another game (or trade a Vulpix and evolve it with a fire stone)
There is a very dark cave in the soulsilver realm that allows you to remotley find the fire stone in heartgold. first u must purchase soulsilver. The next step is up to you, but it will help if you have the firestone in heartgold ok. that's how i did it