The link I posted is particularly useful for rural areas where the name of the village is not shown at the top of the 1939 page.
My grandmother is in Buckinghmshire, Winslow district ref 147/3, using TNA link I've established she is in Whaddon
RG 14/7955 1911 Registration Sub-District: Winslow Civil Parish, Township or Place: Whaddon RD 147 RS 1 ED 3
She lives in a cottage, without a street name.