If you are interested in old maps here are some additional links for you.
who has a large collection of old maps for sale including some very high quality framed maps.
has an exceptionally large stock of Ordnance Survey maps. All dates from 1801-2006, all scales and all areas of England, Wales, Scotland and Ireland."
The Charles Close Society
for the study of Ordnance Survey Maps, who amongst other things sell what must be the definitive book on these maps -
Popular Maps. The Ordnance Survey Popular Edition One Inch Map of England and Wales 1919-1926
by Yolande Hodson
Other old maps sites
Hipkiss' old map site
The Old Map site
, some old road maps of the UK
The National Library of Scotland
, this link is to the "Popular Edition" index, but there are many older and newer maps available.