Local organisations

The Blake Society at St James’s, 
http://www.blakesociety.org/index.php

Friends of Hyde Park and Kensington Gardens, 
http://www.friendshpkg.org.uk/

The Marylebone Association, 
http://www.marylebone.org/

Paddington Waterways and Maida Vale Society,
http://www.paddingtonwaterways.com/index.php

St John’s Wood Society,
https://www.stjohnswood.org.uk/

St Marylebone Society,
http://www.stmarylebone-society.org/

Soho Society,
http://www.thesohosociety.org.uk/

The Thorney Island Society and Friends of St James's Park and Green Park,
http://thethorneyislandsociety.org.uk/ttis/

Other online databases of archival holdings

The National Archives Discovery Catalogue

https://discovery.nationalarchives.gov.uk/advanced-search

Provides a single point of access to search the holdings of over 2,500 different archive repositories in the UK

Archives Hub, 
http://www.archiveshub.ac.uk/
Provides a single point of access to descriptions of collections that are available for research in UK universities and colleges

AIM25,
https://aim25.com/
Searches catalogues for archive repositories within London

London Metropolitan Archives,
https://www.cityoflondon.gov.uk/things-to-do/london-metropolitan-archives/Pages/default.aspx
Home of the records of the City of London and organisations such as Greater London Council, other official records (e.g. court records) in the Westminster area, and parish records for the Marylebone and Paddington areas amongst others

Digital collections (subscription sites)

Ancestry,
www.ancestry.co.uk

Find My Past,
www.findmypast.co.uk