Get RSS feed from iTunes podcast links
Solution 1:
You should first subscribe to the Podcast using iTunes, then open your iTunes library.
If you go to your Podcasts listing in your iTunes library, you will see a list of the Podcasts you subscribe to. Right-click on the Podcast you want to copy the URL of and select "Copy Podcast URL". This will copy the URL to the RSS feed of the Podcast into your clipboard. You can then paste that link into whatever other application you are using.
Solution 2:
You can use the following "small tool" I created to do this:
Itunes podcast link extractor (Just enter an iTunes podcast URL in the input field)
How it works if you prefer to do it manually:
Extract the Id from the link with a regex or somethin else
EX: https://itunes.apple.com/podcast/state-trance-official-podcast/id260190086
load this link with the ID https://itunes.apple.com/lookup?id=260190086&entity=podcast
Get the feedUrl from this json file.
The &entity=podcast is not necessary but it may help
Country code may be required outside the US, eg: &country=au
Solution 3:
This works also: http://picklemonkey.net/feedflipper-home/ You can even see the original iTunes feed when you open the generated feed in your browser.
Solution 4:
I believe all the existing answers are mistaken. The itms protocol is used when a podcast is not listed on iTunes at all. It's used as a shortcut to subscribe a regular RSS feed that isn't on iTunes. It's a way to allow someone to subscribe to iTunes without having the feed listed in the directory.
It works simply by replacing the http:// protocol prefix of an RSS feed URL with itms:// So, if you'd like to get the regular RSS feed of a show that's linking to itms, just replace the itms with http.
Here's an example: A show I help produce is called Keith and The Girl. Their RSS feed is http://www.keithandthegirl.com/rss Their iTunes link listing is https://itunes.apple.com/us/podcast/keith-girl-comedy-talk-show/id253167631?mt=2&ign-mpt=uo%3D4
However, you can subscribe to the RSS feed directly by replacing the http in the RSS feed url with ITMS like so itms://www.keithandthegirl.com/rss (SE won't let me make that link clickable but you get the idea)
So, now you see that ITMS and HTTP are interchangeable. Whenever you encounter an ITMS link, just replace it with HTTP.