The thing is, who actually owns the copyright to the original manuals and supporting books that came bundled with the actual Amigas? Does anyone still own their copyright?

I was initially thinking more about the independent non-official authors and publishers such as Bruce Smith. I've already emailed Bruce Smith to ask about his books, and from his blog site it would seem to indicate that Bruce Smith Books Publications is no longer in existence, which might be a good thing for us. I can imagine publishers that are still publishing new books would be less likely to allow us to reproduce their publications for download.