First of all, its ENTRALINK. Turn on your C-Gear. On of the three options has Entralink, I forget which, but they do. Keep trying till you find it.
For a list of all known Pokemon, see the related link.
wifi battles battle subway dress up do elite four again link battle (if fiends have pokemon black or white)
Using a GBA Link cable.
The related link below shows a complete list of all the new Pokémon available in Pokémon Black and White Version.
You can not counter Tornadous in white, he's only in black. The only way to get him is to link trade
No you cannot. It is one of many Pokemons exclusive to Pokemon White. If you want a full list of those, Google "version-exclusive Pokemon" and click the Bulbapedia link.
Pokemon global link is free but you do need a copy of the pokemon black version or white version, and also a DSI. That will cost some money but I think that It's worth it. You can get berries and items and pokemon (too bad they are all lv.10) and send them into your game. You will also need a pokemon trainer club account and the C-Gear. Click on the Game Sync button in the online section. The Pokemon global link is out now!
double click on a download link to get the file and extract it with winzip, winrar or jzip program.
Yes, but you'll need a link cable into the Gameboy to trade.
Yes you can. Use a link cable.
You have to link trade a pokemon
I put a link to guide on all the legendary pokemon in Pokemon Black in the related links.