i like the second one the best. I'm pretty certain that most of the manuals are out there in PDF format already. Organizing / finding them all would be a bit of work, but it's doable.
There's a bit of a copyright problem, there- You can't just scan in documents and offer them out as PDF, hoping for the best.
The way early-stage companies sometimes get around this is to allow user-uploads, and then close their eyes and humm to avoid knowing what's in them. See: Youtube, Scribd.
But why would companies care about their manuals being in users hands? Imagine the app launches first, then starts negotiating with the companies - I doubt that one would get sued.
