Anglesey Equestrian Centre (at the western end of the RAF Valley runway) has closed down. Shame because they had some nice stables and a good sized arena and close to ride on the beach. Haven't been to Stabl Wen in Bodedern for a long time but it used to be a bit of a dump. I believe Ned Pritchard in Gwalchmai has some liveries and he also has an indoor school and holds some shows there. Trevor Stables just the other side of Bodedern does livery and has a small indoor school. Charles Carnell in Rhosneigr has stables. Not sure if he does livery though or even if he has any horses any more. If none of these suit then there are lots of farms and small holdings around that would probably do DIY and then you'd have to box to have lessons somewhere if you wanted a menage. Stick some adverts up in the local feed merchants or local paper.
Charles Carnell doesnt do livery any more, riding school closed, stabl wen has all the facilities but grazing isnt great?? Neds has some liveries and indoor working farm also! Trevor has nice facilities and stables, not sure on the amount of land for summer grazing though? Pen Y Graig in Gwalchmai do livery also, pm me for more info?