It has been said that the Pokemon Global Link will launch its opening this March 30. Unfortunatey, it will still not be open because of the Tohoku Earthquake that hits Japan. There's no announcment yet when will be the exact date the Pokemon Global link will be open. As of now you must play the "Befriend a Pokemon!" mini game of Pokemon.com so that when the Global Link will be available and when you access the dream world, you can have one of Eevee's seven evolutions. Just complete the 4 levels and you can now choose what evolution that you want depening on the action of the game.