Replay AV can capture audio/video streams and convert your recordings to iPod format

How to convert streaming audio/video to iPod m4a audio, iPod bookmarkable .m4b audio, iPod .mp4 video (and add to iTunes) after capturing them with Replay AV

• In the Replay AV open the Properties window for the show which files should be converted after capturing.
• Select the Basic tab. Select the format you want to convert to (such as iPod m4a, iPod m4b, iPod video,...) in the After recording, convert to combo box.
• Select the Output tab. Mark the Keep copy of the original file after converting check box (if you wanna keep the original recordings).
• On the Output tab check Add to iTunes library if needed.
• Click the OK button.

You might also need to change the DirectShow options of the Replay Converter

• Launch the Replay Converter
• Hit the Options button. Hit the Audio conversion options button.
• In the Audio Conversion Options mark Real (.ra) and Other checkboxes to use Direct Show when converting from these audio formats.
• Hit the OK button. Hit the OK button.

Another tutorial:
How to Capture Video and Add it to Your iPod touch or iPhone with Replay AV