Search the historical London street directory and pub history site by surname, street or pub name; you will find many obscure early street addresses in London through the Victorian pub history of London and early parish and licensing records on this site. Most records are before 1944 plus some modern detail, and lots of pictures.
London Street Listings Index in 1921.
Johnson street Westminster (SW1) (Westminster), 21 Horseferry road
4 Bird William, coal dealer
42 Paviors Arms, William Edward Crane
37 Bevan William Charles, greengrocer
43 Army & Navy Co-operative Socirty Limited (manufactory)