Check out this quick tutorial of Jared Bienz on creating lookless controls for WPF and Silverlight.
This screencast is a continuation of a previous screencast entitled “Skins for WPF and Silverlight”. In this session we go beyond skinning built-in controls and learn what’s required to create our own skinnable (or ‘lookless’) controls.
This screencast assumes existing knowledge about styles and templates, so if you aren’t up to speed on those topics please consider watching the skinning screencast first.