How do you get internet Multiplayer?
Lol...
That's kind of the problem in my opinion with Unity (That and AI)...
But,
http://forum.unity3d.com/threads/29015-UniKnowledge-entry-Unity-Networking-the-Zero-to-Hero-guide http://unity3d.com/support/documentation/Components/Network%20Reference%20Guide.html http://unity3d.com/support/resources/example-projects/networking-example
Get reading...
Another thing to look up perhaps:
http://www.smartfoxserver.com/
It's kind of complicated... But you CAN do it... Just networking in general is a little tough (In my opinion)...
Good luck though! =)