First thing is that a file (music or otherwise) cannot be "made into a podcast" by changing the media type. It never could be.
Poeple have told me, in past discussions on this forum, and in very strong terms, that I'm wrong about this, but the fact remains that something is only a Podcast if it has been downloaded from the internet "as a Podcast", which means: "through the Podcast delivery method".
Perhaps what has happened is that Apple have fixed something that was incorrect (being able to change something into a Podcast simply by changing the Media Type).
As for you actual issue, tagging something so that you can play it on your iPod; I'm not sure I understand what the problem is.
Okay, so you have recorded some audio, which is now presumably on your computer as an MP3 file. Did you add any tagging information when you created the MP3 file, for example in Audacity? If you did, or if you can, then that should show up in iTunes. If not, you can modify the tagging once the file has been imported into your iTunes Library.
Presumably you could import the audio before iTunes 11, and that procedure hasn't changed as far as I'm aware, so you should still be able to import the recordings. Once imported, it can be played in iTunes, even before changing any of the tag information. It can also be added to an iPhone.
So what is it about the tagging that you don't like, apart from not being able to "make it a Podcast". How does making it a Podcast change anything?
I ask, so that I can understand. Then I can possibly offer another solution.