I have collated all my documentation and built a webpage of the waveforms to/from the ECU which can be found at; http://users.actrix.co.nz/richardm/Pages/waveforms.htm. Most of these came from the Altezza documentation, but should apply to any late model Toyota, and I would assume a lot of early model ones.
If anyone has access to this sort of documentation for other Toyotas, let me know and I'll add it to the page.