Where do you find larvesta in Pokemon black?

Answer 1

There are two ways to get Larvesta:

1. On route 17, a Ranger in the P2 lab will give you a Larvesta egg if you have an extra space in your party.
2. Capture Volcarona after beating the main storyline in the deepest room of Relic Castle and breed it. You get a Larvesta Egg

Either way, you end up with a Larvesta Egg. Larvesta's don't appear in the wild, unless there is some ActionReplay code for it. Though, I personally don't recommend using an ActionReplay because it messes with your game.