Many accurate 1921 census transcriptions have already been added to the pub history site, including London, and parts of Middlesex. If you can contribute to the site, send me some details to Kevan, along with some description of the specific property.
A listing of the Public Houses, Publicans and Public House address in 1839
You cannot link to all pages from the index, it points the start page for a letter, then use next - or alternatively just use the search engine to search for your ancestors!