Bruji

Just that. Put the book on a TWAIN scanner, hit "Scan cover" and have the image in the cover field (because using the built-in iSight camera is pretty bad for this).

Thank you for the feedback, I have written it down as I do know that Mac OS X used to ship with some built in support for TWAIN so I'll see if there are possibilities there for integration.

For the most part the dedicated software for the scanners tend to do a better job of scanning and detecting images. Bookpedia makes it easy to drag and drop the resulting scan from the TWAIN software over to the image well to set as the cover for the selected book.

FWIW, both Image Capture and Preview have scanner support built-in--and, of course, "Print & Scan" is a Preference Pane (was Print & Fax up to 10.6, changed to Print & Scan in 10.7 and later). But, obviously, it's easier to be able to bypass running a separate app that serves no other purpose.