I host over 30 music / podcast feeds on my digitalocean server (very inexpensive) as well as ipfs.
If you visit https://ipfspodcasting.net/Feed all but 11 "podcasts" in the top half are hosted by me and are served through IPFS.
All you really need is a place to host your RSS file and songs that is publicly available. Then submit it to podcastindex,org
ipfspodcasting.net provides a redirect that fetches the mp3 from an ipfs node and serves it through a public gateway automatically.
Here is an example of how the redirect works.
If you put ipfs podcasting into your splits then it incentivises ipfs nodes to pin your mp3 file as they get a portion of the split.
As far as needing a domain; I don't know of any podcast players that support the ipfs protocol natively so the ipfspodcasting redirect to to gateway is the only way that I know of to get ipfs to work.
I'm not sure if this post answers your questions or was helpful. Hopefully it was 🙂