Firestorm games has vol 2 for around £30
https://www.firestormgames.co.uk/angel-giraldez-masterclass-volume-2
As for volume 1 I can't find it anywhere either - wayland, firestorm, ebay and amazon. I also tried looking on Abe books but it doesnt' even pick up either volume
www.abebooks.co.
uk
though you could try more search terms and the ISBN if you can find it.
Element Games did list it, but only as unavailable. I suspect that they only did a limited series of print runs and once the stock was gone the product was gone. You might ask around the Infinity forums and even drop them an email to find out for sure. On the latter you could even enquire about the possibility of a digital release of the book.