Control unity3D from another program

hi all

i have used so far Ogre3D for my applications in order to render object to a scene. now i want to switch my engine to Unity so... basically i need to be able to open a window from my Visual Studio application and to add or remove object in my scene. i am also need to have control on my camera position and orientation, surely i will have to write all of this methods myself.

if someone could give me a reference it will be great, even books or toturials will be awesome.