SliverLight Formally known as "WPF/E" is now released as beta version, more resources is found in microsoft web site
Microsoft ASP.NET Futures (May 2007): Compatible with both Visual Studio 2005 and Visual Studio “Orcas,” this package contains ASP.NET-based Silverlight controls.
Microsoft Silverlight 1.0 Beta Software Development Kit (SDK): create Silverlight Web experiences that target Silverlight 1.0 Beta.
The SDK contains documentation, samples along with templates for
Microsoft Visual Studio.
Microsoft Silverlight 1.1 Alpha Software Development Kit (SDK): Download this SDK to create Silverlight Web experiences that target
Silverlight 1.1 Alpha. The SDK contains documentation and samples.