LSOA boundaries for Sheffield
Downloaded shapefile from Lower Layer Super Output Areas (December 2011) Generalised Clipped Boundaries in England and Wales.
Then converted it to CSV using shpit.
Then extracted just the Sheffield part using sed to make the
file
Lower_Layer_Super_Output_Areas_December_2011_Generalised_Clipped__Boundaries_in_Sheffield.csv
That file has coordinates in British National Grid;
the Python program bin/convertWGS84.py
transforms them to WGS 84 (suitable for web)
using pyproj.
It creates the file
Lower_Layer_Super_Output_Areas_December_2011_Generalised_Clipped__Boundaries_in_SheffieldWGS84.csv
That file has two additional, final, columns, called lon and lat
(for longitude and latitude).