Since 1997 Taylor University has held The Frances White Ewbank Colloquium on C.S. Lewis & Friends nearly every two years (they skipped 2003). In addition to having great guest speakers over the years, this meeting also provides the opportunity for individuals to present a twenty minute address. Then, not long after the event, the corresponding papers based on those shorter talks are printed in a volume called INKLINGS FOREVER. Plus, nearly all of those essays are available online for free!
Annual C. S. Lewis Lecture (TN)
While there are a variety of places online to listen to audio lectures about the life and work of C.S. Lewis none that I’m aware of have a archive going back over 30 years. That’s the case for a annual lecture series held at the University of Tennessee at Chattanooga. While the site hasn’t obviously existed that long, it collects all the available recordings dating back to 1983 when the inaugural lecture was given by the Dr. Paul Holmer from Yale University.
As time of this posting the site does have several shortcomings. The audio only played well on Internet Explorer browser on my computer, but fortunately a quick check on my Android phone yielded no difficulty.