Visual Studio 2008 SP1 用 Microsoft Silverlight 2 Tools
http://www.microsoft.com/downloads/ja-jp/details.aspx?FamilyID=c22d6a7b-546f-4407-8ef6-d60c8ee221ed
http://download.microsoft.com/download/a/1/e/a1eccacc-dfe2-45ff-80b1-c6a80c69ecb2/Silverlight_Tools.exe