I'm wondering if anyone knows off-hand where the data for the frames will reside?
I'm assuming you mean, where the data in the AVI is? You can read up on the specs if you want to read directly from file: (RIFF) and (AVI). The actual image data is in sub-chunks under the "movi" list.

Also, from what I read, a lot of people working with video use OpenCV to help with processing, it might be worth looking into. (Though I admit this is definitely not my area of expertise )