Autodesk supports several Developer Center web pages that contain general information about programming the various Autodesk products that support an API. With each major release these sites are updated, and occasionally there are updates in between releases. The update to Inventor’s Developer Center site for Inventor 2013 is now available. See http://www.autodesk.com/developinventor. You’ll also see links on the left-hand side of the page to the pages of the other Autodesk products. These sites aren’t meant to have all the information you’ll ever need but are intended to help get you started programming a product by providing a general overview of the technology and links to existing resources.