Browsing through Google Books (full editions) I have come across "The Imperial Guide with picturesque plans of the great post roads" by James Barker dated 1801/2. It has several fascinating illustrations with small pen and ink drawings of the towns and great houses along the route the 'post roads'. The illustration I am looking at goes from Coventry to Stony Stratford and has 28 of these small drawings.These include illustrations of Towcester, Easton Neston House, Stony Stratford and some local villages that I have not come across before. Also includes windmills. It covers much of the country and is worth a look. Book can be downloaded as a pdf but illustrations loose some detail.