Here are links for radio interviews put together by my friend Frank Smith. The first is for Led Zeppelin era, the second for post-Zeppelin and the third is miscellaneous. Frank says this is still a work-in-progress as he continues to consolidate loose ends and make additions.
I will forward any links to interviews not on Franks' lists that you have if you let me know what they are. You can post the links (and description please) in the comments, below. Meanwhile - there are 112 interviews so far for you to enjoy.
These links are also posted on the RESOURCES page so you can always find them.