Never heard of a single rescue centre round where I live! I'm not going to go as far as Cardiff to ride, which means that there are only three riding stables within a reasonable distance. I don't know what livery places there are. Where I ride, you have to make a big commitment - their volunteers are known as 'free riders' and you work from 8:30am to 5:30pm, with a free lesson during the day. You can't really just come in and do a bit now and then; they have top horses there and need properly trained people looking after them on a reliable schedule. Though I do know that there's one woman who comes in every Thursday to groom Charlie Brown, because she saw him one evening and thought he looked lonely xD
The other two stables are in not-so-good condition, shall we say, which makes me reluctant to help out at them. Sure, they might be more willing to let a total beginner come in and help but I'd rather be somewhere safe and trustworthy, with good practices.
Right now, as a total beginner, I don't know much about looking after horses, which makes me more of a liability than a help. But I'm slowly learning, with the help of my friend Charlie (different Charlie to the horse mentioned above xD this one's a human) and her horse Luca, and I am hoping that maybe I'll be able to loan a horse on working livery for a few weeks at the end of the summer! Until then, I'm booked in on a regular slot on Thursdays so I've at least got one lesson a week ... and HorseForum isn't down anymore so I can still come on here