The German trial versions  of Microsoft Expression Studio  are now available. The full versions will be available in about 6 weeks, Expression Web is already available.
For further details visit the Microsoft Expression Web site . If you have a MSDN subscription you will find Expression Studio, Blend and Web in your downloads.
Note: to develop Silverlight 1.1 applications  you need Microsoft Expression Blend 2  which is currently available as a preview version (free trial).