Well, I have not gone deeper into the nuances of sake, but you don’t have to go to Japan to try them out. thisislondon.co.uk has a feature on the best saki (?) bars in London. One of them even lets you buy a sampler, letting you taste six varieties if there are two of you.
Wikipedia has more on sake if you’re interested.
And if you are looking for cider, it seems like the Green Man is your place.
I’d rather have a pint of bitter, please.