At Amazon uk, actually any amazon, i assume nobody buys directly from the first page at "amazon price", as the prices never make much sense, you go below to one of the used or new link options, and then get very good deals, for eg. Notter's book is 30.5 gbp for new, before shipping. Unfortunately not every "shop option" sends to my country, i assume your life is much easier in that sense, and shipping costs are very low if you are in the UK (and Europe..).
I think Book depository used to have better prices in the past, but lost a lot of ground in the last couple of years, as it seems that the options i mention from Amazon uk site (below the "amazon price") became signifacently cheaper in past years, without a proper respone from BD.. My feeling and opinion..