Creative Commons - FREE
Creative Commons, together with Archive.org, offer you the option to host your content for free. This is directed towards CC-licensed or open-source audio, so your own speech or your own music. Don’t use it to host illegal/copyright-troubled content.
£50/year (or £4/month)
if you’re already a subscriber to Apple’s .Mac program, this is an easy option. It is not the fastest or most reliable option.
starts at £2.50/month (up to £15)
built for podcasting: based on the #MB you add per month, not on the #GB downloaded per month (so the cost is predictable). Has detailed statistics (although some graphics would be nice). “Liberated Syndication is podcasting made easy”
£3/month (2-year subscription)
2 GB storage, 75 GB/month bandwidth. Is a general purpose hoster, so if you want to add the actual podcast blog to it, you can (you can add a WordPress blog through the Fantastico interface)
for the bigger fish: 10GB of storage, 100GB/month bandwidth. If even this is not enough, you can go up to a £50/mon fully dedicated server: 60GB storage, 1000GB bandwidth. EV1Servers VPS