Yes. The pokemon you battle with your starter when you "save" Prof. Rowan is a Starly, and you can find other Starly and Shinx and Bidoof on the route above your hometown.
SPRITOMB you can see it in the elite four.Champion Cynthia has it.It is her first pokemon.
the Pokemon in diamond are sinnoh Pokemon i suggest http://Pokemon.marriland.com/diamond_pearl/pokedex to see all of them
The only way you can see all the Pokemon on diamond is by going into the GTS and global trade different Pokemon.
No all you have to do is SEE the first 150 Pokemon then you shall get the national dex..
you have to catch all of the pokemon in diamond or SEE all of the pokemon
A Pokemon
fight every trainer or TRAVEL that's what your journey is about travling to new places and discovering Pokemon
The Pokemon you see do not go in your pokedex.
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No, you cannot see every Pokémon in the National Dex in Pokémon Diamond however you can see every Pokémon in the regional Sinnoh Dex in Pokémon Diamond.
for diamond and pearl there are 150 Pokemon u need to see . in plat nium u neeed to see 210 Pokemon.
You see it in the Pokemon league The champion has it