Newbie needs help with DirectX.

Question

I dont know how to get this right C:\DXSDK\SAMPLES\C#\DIRECT3D\TUTORIALS\TUTORIAL1\CreateDevice.cs(13): The type or namespace name 'DirectX' does not exist in the class or namespace 'Microsoft' (are you missing an assembly reference?) I know that namespace is the part of the framework, but the DirectX API. But how do i fix it? I tried to add Reference, but I cant find such thing. please help, thank you