From Heaven to Hell, by Beryl Brennan, is the story of the 100,000 a year galgos, (spanish greyhounds), including our ex-racers and many irish greyhounds which end up in Spain, the annual holocaust, and the work of the spanish and european rescues which try to help them. All proceeds of the book go to these rescues. There is an online version and a print version, from Scoot Books, who published this for free. You can find it at http://www.scootbooks.com
It's an interesting read,with a lot about the political and cultural influences which work against welfare improvements, but have a BIG box of hankies at the ready. I think the point which probably shocked me most is that you cannot even just go for a walk with your pet greyhound in certain parts of Spain as the risk of it just being snatched from your hands is so great, and you'll be followed home by thieves to find out where the hound is kept.