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though the book cost me £49 on ebay as my price vc2s artook cost me the slightly less price
honestly it was a miracle being auctioned of on ebay because amazon wasn't doing any favours https://www.amazon.co.uk/Valkyria-Chronicles-Design-Archive-Sega/dp/1926778162/ref=sr_1_1?ie=UTF8&qid=1544123212&sr=8-1&keywords=valkyria+chronicles+design (don't buy it unless your truly devoted)
English one, found the link: https://www.amazon.com/-/es/Sega/dp/1926778162
Looks like while the VC1 got cheaper, the VC3 artbook went to the moon.
And yes, I know there are cheaper places, but I got mines using Amazon.
To answer 2, there are a few maps, but not of much use in the official art book Sega released:
It used to be only $50, but now that it is out of print prices jumped up.