Hi, if you are talking about these Videos, " http://web.me.com/rhino3dtv/GH/GH.html ", the GH definitions and the 3DM files can be found on the Upper Right Corner of the same page that you view the video. For GH definitions, you would see a small Green Circle with the Grasshopper inside, if you click that icon, you would download the definition, and also, if you see the Head of Rhino, click that icon and you would be able to download the 3DM file for that exercise... I do hope you can find those two icons... NOTE: No all the videos have these icons ok