I don't know if anyone else has been watching the wonderful series on BBC4 'In Their Own Words: British Novelists', charting the British novel through the twentieth century with the help of archive footage (mostly from the Beeb itself) and the usual talking heads, but -- disappointed that the series had come to a close -- I had a click around on the BBC website and stumbled across this
It's a collection of archived interviews with the famous names of 20th century British literature. Some (most?) are rather sizeable; such as a thirty minute interview with J.R.R. Tolkien from the late sixties
. Unfortunately, the footage is only available in the UK and in those various places with an opt-in to the BBC (as I believe Ireland has); but if you can access it then it's well worth a look.
The BBC4 series is still available on the iPlayer
, should you be interested.