1) Where should she go to buy British SF novels? It doesn't have to be a genre-specialty bookstore -- I just don't want to walk into the equivalent of an airport bookshop and say, "Oh, look, they've got a quarter of the Terry Pratchett we've got at home and some Dan freaking Brown novels," and walk out again.
2) What's out in the UK but not (or not yet) in the US that she should look for? (Speculative fiction in particular, but other genres welcome with some kind of description of what, exactly, it is I'd be dealing with. Er, she'd be dealing with.)