I got the most recent 4 on his site about a week ago. Haven't see the others. They were *****ing about the cost of hosting them on one, so maybe they pulled down back issues?
If you find them, please post. He's a funny guy.
Edit: here's #9...
http://podcast.rickygervais.com/episode9january30.mp3
Edit 2: Found them all on usenet. Got a newsreader? Look in alt.binaries.sounds.mp3.comedy