Yale has recently posted seven of its undergraduate courses in an especially accessible format. Yale has done a beautiful job of creating a complete downloadable package for each course. You can get audio and video recordings of each lecture as well as transcripts and supplemental materials.
If you are new to the business of downloading audio files, here is a quick tutorial for users of Windows computers. Point with your mouse at the download link, and right-click the mouse. On the context menu that appears, click on “save Link as,” and Windows should then give you the option of where to store the file. Tell Windows the filename and file location you want, and click “save.” For the Yale courses you will also need a program which will “unzip” the compressed file that you downloaded. A good candidate is the free program Jzip.