Amigofish is pretty badly organized. There's no topical directory of the shows, just a very long listing, all 733 pages of it. Bleah.
UPDATE: The owner of amigofish saw this review and says I don't get it. Their system is about users together reviewing and ranking podcasts. So it's a wisdom of the crowd play. And I agree with his sentiment that a predefined hierarchy by the administrator of a directory isn't always helpful, and that you can find a lot of useful things from a crowd voting on things.