Following the advice of this article, I downloaded Blender version 2.73 from here: https://download.blender.org/release/. I did this to avoid any confusion from using different Blender versions from the instructor. Ironically, it seems this has happened anyway.
Version 2.73a doesn't seem to have an Inset Faces tool, and I don't see any place to download 2.73.8, which is used in the video. Perhaps you could link to the appropriate version of Blender in the course description?
Anyway, not a super big deal, just wanted to let you guys know.