I am wanting to create some of my own objects on ArchiCAD, and since this is a community of people creating and uploading their own BIM object creations I thought this would be a great place to get started!
Found this book online, only one that was available for viewing for free so maybe it's worth a shot? http://www.scribd.com/doc/35089318/Object-Making-With-ArchiCAD 2 More Answers