You can only get it by transferring it from a copy of Pokémon Ruby, Sapphire, Emerald, LeafGreen or FireRed. You must have completed the Elite 4 in Diamond and then go to Sandgem town and surf down and go right, there will be a building at the end of the route called the pal park. You must have The older version if your DS slot 2 and then save and quit and go to the main menu where it will say "Transfer from Ruby"
You can only find Nidoran in Pokemon White Version. I heard the more people you bring from Black City to White Forest, the more people and different types of Pokemon. You cannot catch any Pokemon in Black City due to there is no grass, but you can battle many people. Also, you might want to check Pokemon Outbreaks at the gate's Electric Bill Board. You never know what Pokemon might be there... one time I found a Farfetch'd, Houndour, and some other neat Pokemon. :) So make sure to check those, too.
Both male and female are on Route 4
Try looking on the route west of viridian city.
NIDORAN evolves into NIDORINO and it evolves into NIDOKING. It is a great Pokemon infact i am training one, good luck.
Goldeen/Seaking, Nidoran/Nidorino, Nidoran/Nidorina and Rhyhorn/Rhydon learn it.
Nidoran Female and Male both evolve at Level 16.
Go to White Forest when Ken is the resident, if he is, use Entralink to go to Black City from Pokemon Black and you'll receive Nidoran.
At The Pokemon Safari In Fuschia City
Nidoran Male and Female can be found in these places: The route west of viridian city and the safari zone.
You can find Nidoran in route 3 (sometimes even Nidorino\Nidorina) and the Safari Zone in Fuchia city.
Use Pokerader on route 201
Both male and female are on Route 4
it appers on route 201 (mass out break)
You go to White Forest when Ken is the resident, then use Entralink to Pokemon Black and go to Black City, then he should be there to give it to you.
In the safari zone in Fusia city or on route 3 in the midlle of pewter city and mt-moon but it is really hard to find a nidoran(male) i found a nidoran on route 3 but i killed it so get a Pokemon that will help you
Yes, the female nidoran is blue and male nidoran is purple
In Route 36 hope i helped
Try looking on the route west of viridian city.