I have updated my maps of English place-name element distribution (first done in 2005) at http://keithbriggs.info/English_placename_element_distribution.html.
Many more names are now included, including those in Scotland. A simpler, unlabelled version of any map may be obtained by putting a 0 (zero) in the pdf file name (obtained by clicking on the thumbnail png image); e.g. http://keithbriggs.info/EPN_maps/ton.pdf is the full labelled map, but http://keithbriggs.info/EPN_maps/ton0.pdf gives something like this:
Why is -ton scarce in a big ring around London?
Also updated recently: http://keithbriggs.info/Nomina_contents.html,
and http://keithbriggs.info/Roman_road_maps.html (several
roads were missing, including the important one from Salisbury to
Winchester).
Keith
PS: the outline of the Isle of Man is missing; I'll fix this
soon.