Don't cry Hillview there's plenty out there to be done it's just a case of getting your name about and asking.
Did think that myself Bionic, tractor driving is normally quite sought after as part of normal farm work
I have the same sort of experience by the sounds of it, apart from managing my own farm I help other farmers, relief milking, managing their farms when they are away, feeding beef and sheep, helping with dagging/worming/shearing sheep, sileage (if you don't want to do the tractor work there are always pits to cover) stone picking, calf/lamb rearing, lambing, mucking out, the world is your oyster. I also test cattle for disease and milk test which is great if you don't mind the early hours.
Regarding horses there are quite frequently people looking for grooms etc, if you can break you could offer that service also getting horses ready for competition etc