Question

Where do I find a Leaf Stone in Pokemon Black?

Answer 1

On one of the harbours in Castelia City, someone asks you which of the elemental monkeys you were given as a gift. Choose 'Pansage' (whether you got that one or not) and they will give you a Leaf Stone.

You can also find them in dust clouds (rare spots) in the various caves, or by showing all the Deerling forms to the scientist on route 6.

Answer 2

Another place to find a leafstone is on route 6 there will be three pokeballs on the ground two of them are wild pokemon and one is a leafstone

Answer 3

Non-repeatable
- Castelia City (from a Scientist on Thumb Pier)
- Route 6 (show a Scientist all the Deerling forms)
- Route 6 (between the Parasol Lady and Pokemon Ranger)

Repeatable
- Dust clouds
- Black City/White Forest (from Karenna; $10,000)

Leaf Stone (Bulbapedia)

Answer 4

Http://www.serebii.net/blackwhite/items.shtml

Go down to "Evolutionary items on that page, find Leaf STone, and it shows you the Locations. The easiest is Buy it in Black City.