John and Yoder,
Very cool finds! You won't believe this, but in the past few days I've been wondering about the availability of such things for the iPod Touch/iPad, and after checking these out, I'm very glad to see these sorts of things becoming available. I have an iPod Touch 4g, and just very recently got a new iPad2, so now to see how much of this stuff will work with VoiceOver.
I also found this digital multimeter for the Pod/Pad that will be coming out in a few weeks:
http://www.redfishinstruments.com/
I'm reserving mine today.
John, I also checked out the audio tools, but it looks like the iAudioInterface box is no longer being made, so don't know how useful this software is without it. Maybe they have a new one in the pipeline?
-- Jim