We have just launched an all new series over on Channel9 that teaches beginning developers with little programming experience how to develop applications for Windows Phone 7. This series assumes that they have absolutely no knowledge of C#, Silverlight, or mobile development. In just a few hours, they will understand the needed concepts to build applications.
Head over to get started!
I would like to add this tutorial
soonstudios.wordpress.com/.../making-tip-calculator-for-window-phone-7