I love paper maps and buy all my OS and Harveys maps from Dash4it. They are also the best supplier for Cicerone walking guides. They are the cheapest I have found on the internet and with immediate despatch on ordering and Royal Mail first class / 24 Tracked delivery (free assuming you buy the requisite amount) you receive your goods very quickly. If a map is not in stock, in my experience you will still receive your order within a few days. Overall superb service.