Records for Civil Defence work were held locally, and may not have survived – check local authority archives for more information about this. If a Civil Defence member was eligible for the Defence Medal (criteria was complicated but basically three years continuous service in the UK was required for home front awards) records should be held by Defence Medal Applications, Civil Contingencies Secretariat.
Gallantry decorations will be recorded in the London Gazette.
Civil Defence records were held locally, but if a person served with the British Red Cross Society or St John Ambulance, records may be available through the British Red Cross Museum and Archives or The Museum of the Order of St John.
The Wellcome Library has an excellent collection relating to the history of medicine, including registers of doctors and nurses. Some Medical Registers for the war years are available on the subscription website ancestry.org.uk.
Many hospitals have their own archives, although there is a one hundred year restriction on patient information. The Hospital Records Database can be consulted at nationalarchives.gov.uk/hospitalrecords.
National and Auxiliary Fire services
Records for both of these organisations would have been held locally, and may not have survived.
However, London is well covered by the London Fire Brigade Museum. You can apply for London AFS and NFS service records by emailing email@example.com.
Women's Voluntary Service
Some records for members of the Women’s Voluntary Service are held at the WRVS Archive and Heritage Collection. Their website contains useful information including a roll of honour of members who died during the war.
Police records are likely to be held by the relevant local authority but TNA has some Metropolitan Police records.
An online roll of honour for the Metropolitan Police can be found here.
Home Guard records are very brief.
85,000 records for County Durham Home Guard have been digitised by TNA. These are available on a pay per view basis at nationalarchives.gov.uk/records/durham-home-guard.htm. The remaining records are available through the Army Personnel Centre and are released to proven next of kin only, for a £30 fee.
You can make an appointment to view the Home Guard List (only officers listed in this) in IWM’s Research Room. A good collection of unit histories is also held.
Home Guard Defence Medal claims can be made through the Ministry of Defence Medal Office.
Also check local archives/libraries for published or unpublished materials.
Women's Land Army
There are no known surviving records for Women’s Land Army members, but the index cards to the original records for England and Wales are available. These can be seen at TNA on microfilm, or you can order a photocopy of the original card through Collections Access at IWM.
The index cards for Scotland are held by The National Archives of Scotland.
County archives or local history collections may also be useful.
Air Transport Auxiliary
Record cards are held by the RAF Museum London.
Royal Aero Club index cards (and some photographs) in the care of the RAF Museum have been digitised and are available through the subscription website ancestry.co.uk/.
No records are known to exist, but the Bevin Boys Association is seeking to compile a list of the 48,000 Bevin Boys who served.
We hold an extensive collection of material relating to the Bevin Boys Conscription Scheme, 1943–1947 (Miscellaneous 2834). This doesn't generally hold lists of names, although it does contain ballotee records from the Midlands area.
The National Coal Mining Museum may also be able to help.
Royal Observer Corps
The Royal Observer Corps spotted and informed on enemy aircraft. It was formed in 1925, and ceased to exist in 1995. There is a museum, although this does not yet have a permanent home. Service records are also held by this organisation, and are available either free to next of kin or for a £10 charge.