You can get all the emulators at http://emulator-zone.com/doc.php/nds/ But I recomend NO$GBA because it is the best one and I have it too.
any DS emulators you can find
No, emulators of any kind may not get WiFi. You should simply buy a DS, or else you will not get the full thrill of a game.
Yes there are various Pokemon channel emulators that are available for download. Some Pokemon channel emulators are available for free.
You cam only trade Pokemon in emulators to another emulator. If you are trying to trade a Pokemon from the emulator to your actual game you can't
There isn't any
No, there are no other regions in Pokemon Diamond.
buy a action replay or cheat cartridge with Pokemon diamond on it
you can play it on many emulators like ideas etc but no$gba's the best and the fastest
No
Umm... sorry if this sounds rude, but of course there are Pokemon in Pokemon Diamond! It's one of the Pokemon games!
There is no Lumineon in diamond
Any Pokemon (includingWailord and Azelf).