More than a month after the release of DirectX 9.0a(Web Installer), Microsoft has now released DirectX 9.0a Redistributable. There are still no signs of DirectX 9.0a SDK.

This download provides the DirectX 9.0a end-user multi-languaged redistributable that developers can include with their product. The redistributable license agreement covers the terms under which developers may use the Redistributable. For full details please review the DirectX SDK EULA.txt and DirectX Redist.txt files located in the license directory.

System Requirements
Supported Operating Systems: Windows 2000, Windows 2000 Service Pack 2, Windows 2000 Service Pack 3, Windows 98, Windows 98 Second Edition, Windows ME, Windows Server 2003, Windows XP

Download DirectX 9.0a
ieXbeta

look here :)
hxxp://download.microsoft.com/download/5/e/4/5e4af63d-4f8f-450a-9f9b-ea00299dbc16/dx90a_sdk_devruntime.exe

maybe the sdk

IB