I have been listening to National Radio's radio replay of interviews not subject to copyright restrictions, done by the Nine to Noon presenter, and Kim Hill for quite some time, so was interested to see what was on offer from the podcast directories.
http://www.radionz.co.nz/audio for those who are interested in listening to National radio programmes.
I looked at podcastpickle, podcastalley and the yahoo audio search.
I liked the yahoo audio search best as it was very clear, and easy to follow and search on.
I did a "library" search in all three directories and found that alot of the material was quite irrelevant. I think a good sense of humour goes along way when searching for material via these directories as there is alot of weird and wonderful (and not so wonderful) material out there.