Go to Snowpoint city, go to the house in the top left corner of the city, inside the house, there is a young, blond-haired girl. Talk to her and she will ask you if you will trade her a medicham (catch in mt coronet). After catching medicham, go back to the house in snowpoint with medicham in your party (doesn't have to be in first slot) and talk to her and say "yes" to trade. Through the trade the girl will give you a haunter nicknamed "gaspar". (To evolve haunter, trade it and it should evolve).
But when you receive haunter, it will be holding an everstone, so it will not evolve into gengar. Take away the everstone, do another trade and then trade it back to get a gengar (as already mentioned). You can also dig up everstones underground
after getting national dex. Hope I helped (PS. I found this out by doing it on platinum, but don't worry, it was tested on diamond and worked.Also works for pearl and platinum.
Only one's I know of is Graveler, Magmar (With a Magmarizer), Machoke, Rhydon (With the protection item), Haunter, Dusclops (With Reaper Cloth). If you know anymore just edit this.
It's called a dusk stone and it evolves murkrow and misdreavus. You can look up more about it on serebii.net.
you can't you have to get poliwhirl and then use a water stone on it [which is underground]
The sun stone was first introduced in the Pokemon Gold and Silver games. This stone evolves Petili, Gloom, and Sunkern.
catch a female snorunt , then use a dawn stone (iron island) on it
It keeps the Pokemon holding it from evolving.
thunder stone
The moon stone is used in Pokemon Diamond to evolve certain Pokemon. You can find one by looking in the Underground.
There is no such thing as a rock stone.
moon stone
You get a leaf stone underground.
In Diamond, you can obtain a Water Stone in the underground in Sunyshore City.
The dawn stone is an item that is used to evolve certain Pokemon in Pokemon Diamond. To get this item, search in Mt. Coronet.
to evolve certain Pokemon
murkrow
evee
the moon stone.