I Need the source packages of Unity 2d to rebuild and run on Qt , the problem is that I'm using Qt on windows right now. and I have no idea how download the Unity 2d on windows 7.
I don't think that Unit 2D is available for Windows. Why don't you install Ubuntu along side Windows, and use it for what you need. For more info on Unity 2D see Unity (user interface).
If you decide to install Ubuntu, then you can get the source packages from Launchpad.