WH Smith is a very well known newsagents here in the uk - pretty much every train station has one and they're also in most major airports.
Stocking newspapers, magazines, general stationery and more - they always sort you out of you need to pick up some light reading material for a journey.
Their book selection is pretty decent if a little pricey and I do always find it funny how their travel section tends to have loads of books on random destinations and not the ones leaving from that airport.
Most times they offer a free bottle of water when buying the telegraph - get on this deal! Refreshment and reading for the same price! read more