Microsoft® Silverlight™ 3 SDK Beta 1

The Microsoft® Silverlight™ 3 SDK contains online documentation,
online samples, libraries and tools for developing Silverlight 3
applications.

To download, click here.

Microsoft® Silverlight™ 3 Tools Beta 1 for Visual Studio 2008 SP1

This package is an add-on for Visual Studio 2008 SP1 to provide
tooling for Microsoft Silverlight 3. It can be installed on top of
either Visual Studio 2008 SP1 or Visual Web Developer 2008 Express with
SP1, and it provides a Silverlight project system for developing
Silverlight applications using C# or Visual Basic.

To download, click here.