現在の最新バージョンはDirectX 12.0 / 11.3 です。
https://www.microsoft.com/ja-jp/directx/
https://support.microsoft.com/ja-jp/kb/179113
http://blogs.msdn.com/b/directx/
https://msdn.microsoft.com/en-us/library/windows/desktop/mt748631
http://www.directxtech.com/

DirectXTK12
https://github.com/Microsoft/DirectXTK12

Games for Windows and the DirectX SDK
http://blogs.msdn.com/b/chuckw/

DirectX Tool Kit
https://directxtk.codeplex.com/

DirectXTex texture processing library
https://directxtex.codeplex.com/

C#でDirectX又はXNA系の情報を探してる人は
MonoGame
http://www.monogame.net/

SharpDX
http://sharpdx.org/