This is a wonderfully heartwarming book by Lynn Reardon, who runs LOPE - Lonestar Outreach to Place Ex-racers, a racehorse rehabilitation and rehoming centre in Texas. She started the centre as a complete horse 'rookie', and her book recounts her ups and downs as she started out, and the characters (mostly equine) she met along the way.
A large chunk of the proceeds from the book sales go to running LOPE, a very worthy cause
http://www.amazon.co.uk/s/ref=nb_ss_5_13?url=search-alias%3Dstripbooks&field-keywords=beyond+the+homestretch&sprefix=beyond+the+ho