I spent some time over Thanksgiving break looking for premade 3D images that I could include in my iBook; having messed around with 3D modeling in high school I know it would take too much time to do it myself (plus I don't have the software anymore). Due to the fact that iBooks Author only accepts 3D files of the COLLADA format my search was made somewhat difficult; the Google-search of 3D images, called "3D Warehouse", has an extensive collection of files but most are incompatible. Eventually my search led me to OurBricks.com, which is a repository of miscellaneous, Creative Commons licensed 3D models, all in COLLADA. I was overjoyed. The objects look very cool when you place them in an iBook and rotate them with your finger gestures-- I think being able to interact with clues will add an important element of interactivity to my mystery novel.