Hi Mike,
I'm sorry, but I don't know of a card that will work with Pear Note. Pear Note uses the standard Quicktime interfaces for video input. For a video device to work with Pear Note (or other apps like iChat, Skype, etc.), the device must provide some software to hook it into Quicktime (in Quicktime parlance, this is called a Sequence Grabber Component). Neither of the cards you mentioned have this, which is why you have to use the software provided by the manufacturer to operate the card. If you could find a card that had such a component, then it should work with Pear Note, though I've never tried it. A card that did this would likely claim to work with lots of software (e.g. iChat and Skype).
I hope that helps. Let me know if you find anything.
Thanks,
Chad