My solution to adding 12", 10" and oversized packaging was simple... I photograph everything using a digital camera fixed to a copystand! I've made a note of the settings I need for each format (ie camera height etc), the base is marked so I put each format in the same position. This way I always get uniform results... no messing around with joining two or more images, just simple cropping and resizing. And it's much faster than scanning as well (at least when doing multiple covers).

Just thought I'd through that into the pot!

Cheers,

David