Info on how to handle USB access for external peripherals?

I've been wanting to write a data logger application to use during my amateur auto racing events. But building the capture hardware and making a small "carputer" always sounded expensive and time consuming. But I just realized the other day that the Wii would be the perfect platform for my idea! Small and with no moving parts, and I can connect two wireless 3-axis accelerometers (Wiimotes) and get some very useful information off them. Anyway, beyond the accelerometers, I would also like to pull input from a USB adapter for the OBDII diagnostic feed from my car and a NEMA data stream from a USB GPS unit.

I see this on Wiibrew [www.wiibrew.org] which looks promising... but there's really no more information. Does anyone know how I can communicate with USB devices connected to the back of the Wii? Any nudge in the right direction would be more than appreciated!

I noticed [www.wiibrew.org] seems to have some useful info, but does the example code apply to oh0? Also, from those who may know, do the examples from the oh1 page apply to what I'm thinking of doing?

Thanks!

Take a peek at libogc's source - specifically - usb.c for low-level USB access, and usbstorage.c for an implementation of USB MSD support. They may help you in figuring out how to do what you want.