A step-by-step walk through on creating your first Windows Phone application. Includes the tools installation, project system, default VS templates,and then a comprehensive twitter search app. Download from here.
On Windows Phone, you get Silverlight 3 plus a few optimizations for phone form-factor, performance, or the Windows Phone User Experience and Design Guidelines. This chapter will walk you through these tweaks and turn you from a (desktop) Silverlight developer into a savvy Windows Phone developer in < 20 minutes. Download from here.