Do you know the horse's registered BSJA name? If so, you can either phone them up and ask them, or if you want the print out you can look via their website - but that will cost you £5 (member) or £10 (non member).
bsja website - horse search. You can just use the broader search by putting in part of the name. It will tell you age and grade but not actual winnings unless you pay.