Summary: The episodes can be found by going here:
Up until mid 2006, This American Life (a popular and awesome radio show on NPR) had "streaming" mp3 files of their archived shows on their website. They had struck a deal with iTunes/Audible.com to sell the shows for download - so they didn't have any great incentive to make free podcasts/.xml feeds available.
Then some enterprising Internet user created an unofficial .xml feed of their archived shows, so that you could download the "streaming" mp3 files to your ipod. It's worth noting of course, that it's almost impossible to make a mp3 file streaming only. All you can do, is make it difficult to download.
And so, for much of 2006, you could either manually download the shows from this address (http://audio.wbez.org/tal/SHOWNUMBER.mp3), which no longer works, or you could use the ultra-nifty unofficial podcast (http://www.redjar.org/radio/tal/archive/).
This American Life's lawyers (or someone there) didn't seem to like this, and sent the podcast guy a cease and desist letter. Stop it, or else. While his unofficial podcast feed went down, their directory structure/naming scheme persisted, and so savvy Internet users were still able to download all the old TAL eposides with a few issues of the "wget" command.
In October of 2006, This American Life announces that they're going to offer free podcasts of their 2 most recent shows. All the old shows will still be available for free, streaming online, or for podcast purchase from the Itunes store/Audible.com
It seemed like a happy compromise.
The only problem was, in the process of doing this, they replaced their streaming mp3 links with a sneaky flash plugin - which made is particularly difficult to figure out where the files are kept - at least by doing a "view source" in the browser...
Today, I wanted to load up my ipod (since I'm flying to New Jersey later) with the TAL episodes that I missed over Xmas... the old method of using 'wget' didn't work, so I fired up wireshark - a packet sniffer - and discovered that TAL has moved to a new directory structure..
I'm happy to share this useful tidbit of info.
This American Life episodes may now be downloaded at http://audio.thisamericanlife.org/jomamashouse/ismymamashouse/
Clearly, someone over there has a sense of humor.