In order to obtain a Razor Fang, you need to be able to trade it from either Heartgold, Soulsilver, or Platinum. Those are the only one's I know that have Razor Fang.
There is no razor fang in emerald as Gliscor does not exist in the third generation.
In order to get a razor claw you need to have Gilgar hold the razor fang at night and level up. You can find a razor fang on Route 214.
route 214
In diamond and pearl you can only get it from battle tower for 48BP and in platinum you can get it from route 214.
on solaceon town down
On Pokemon Pearl: The Razor Fang is located in the garden at Battle Park. It is on the lower left screen. There will be a black belt near the entrance. Go down from the black belt's location, turn left. You should be at a corner. It is there in the pokeball in the corner. ---- In Pokémon Platinum: Go to Route 214 and find the patch of tall grass with the empty space in the bottom right corner. The Razor Fang will be in the bottom right corner.
Find a razor fang: Route 225 {48BP} Battle Frontier
The Razor Fang can be found in Route 214 with the Dowsing Machine and in Route 225, too.
You would might find it at Walmart or at game stop!
u can buy them with battle points
You find it on the floor at Route 13 and the Abundant Shrine. You can also buy it at the Gear Station in Nimbasa City for 48BP.
I think u find it near the last gym