In conjuction with the launch of VSTA at VS Live in San Francisco, where KD Hallman, the Microsoft General Manager for VSTA, delivered a powerful keynote address, Microsoft has also launched the VSTA Developler Center  (http://msdn.microsoft.com/vsta).  

In addition, the VSTA SDK is now available for easy download from the Developer Center.  This provides an easy to access mechanism for downloading the SDK!

 Happy integration!