In the meantime...
Nearly a month since my last (and first) post, I thought I'd post again to show that I haven't disappeared completely.
Recently, I've been trying to get my electronics up to speed. So I've been following the excellent, extensive documents at http://www.allaboutcircuits.com/ - if you export them as PDFs they make a great substitute for books.
I've also started a little java app to read the serial data from the Arduino. This way I can graph the inputs and see what the sensors are up to. Maybe I'll post a it more when I've got something to show.