It's this simple:
- Install Podzilla on your iPod (not all models are supported).
- Boot in to Linux on your iPod.
- Go to Extras > Recordings, choose 8,32,44.1,88.2 or 96kHz the higher, the better quality.
- Record via Line In a microphone or even use your headphones.
- Boot back in to the normal iPod OS plug in to the doc, grab your files from the iPod in the Recordings folder.
Now play with this quick before Apple releases an iPod software update.