I need some resources aimed at a Power User, so an nutshell overview and quick intro into how to manage them in SharePoint Designer would be ACE!
Besttutorial source I know for SharePoint for Power Users is SharePointVideos.com. Asif’s group has great videos that helped me learn a lot of what I know. http://sharepoint-videos.com/category/workflows-out-of-the-box/ – this link will take you to his series on the out of the box workflows. They have lots of SharePoint Designer/InfoPath videos as well.