Regarding the artwork book:
I still haven't seen it for sale outside Corvus Belle, but hopefully it will be at some point.
I got mine through Wayland Games at the time (it included the LE mini too) and got it without problems.
As for the painting book; I recently got it through the Bazaar here at LAF.
While I find it a well laid out and beautiful book, it left me a bit unsatisfied for some reason. There is no denying Mr. Giraldez's skill with the airbrush; the results are stunning, and would be hard to recreate by traditional brush (although I'm sure it can be done). But for some reason, I found some of the traditional brushwork lagging behind.
Don't get me wrong; it's still of very high quality, but in some places not at the level the airbrush techniques are. Most galling I found the face on the Yu Jing TAG pilot; it was almost crude in comparison with the other work in the book. Then again, the face on Tarik Mansuri was awesome.
(but don't get me started on the bust of the girl from the Human Sphere artwork; the painting is flawless, but the sculpting is just... off?)
I must say I was rather intimidated by the airbrush techniques and results and would love to (try to) emulate the results in the book, but for now, that will have to wait because of moneys (getting into airbrushing with even a half decent setup is still rather costly). Still; I will get into it at some point, I'm sure, and that's not a little because of this beautiful book.
One of the greatest things of the book for me though, is the listing of the tools, materials and other items used by the artist. That was very enlightening.
I can recommend the book wholeheartedly too, with the above caveats; it's great, but not without its small flaws. I would certainly buy a next volume, but then immediately when it is released, so I don't have to trawl all channels again to get my LE mini after all (thanks again LAF

).