Book for artists' renderings of extinct species?
With a quick search I was surprise that I could only find


Animals of a Bygone Era: An Illustrated Compendium
Extinct Species
Extinct Animals of the British Isles
Extinct Birds


It looks like there is an open niche to someone who like biology of extinct species and illustrations!

Note all will be of interest to you. None of them seem to offer good quality computer based illustration but rather pencil drawings.