Does anyone know where to download ds roms?

I have found a website but it doesn't have the games i'm looking for.

Sonic Chronicles: The Dark Brotherhood

Pokemon Platinum in english (if so can it be downloaded on windows vista?)

Also can anyone explain to me how to change the language of a ds rom?Does anyone know where to download ds roms?
http://www.nds-roms.com/

http://www.romulation.net/

http://www.dashroms.com/

http://www.dgemu.com/Does anyone know where to download ds roms?
rom bomb
3roms.com or .net