Here's one for the font of all knowledge.

My father-in-law, who past away many years before I met my wife, owned a Talbot 14/45 during the period 1946 to 1948. We are trying to get some more information about it. All we have are some side view pictures but no registration number. I have tried the DVLA and they are absolutely no help at all they just hide behind the Data Protection Act.

I think during that period and up to some time in the 1970's these sort of records I believe were kept in local DVLA offices in hand written registers much like births etc. Does anybody know if these records are kept anywhere.

I assume that you've tried the Talbot Owners Club?

We have

be worth asking Gaydon if they have any, and for other pointers.

http://www.heritage-motor-centre.co.uk/

registration/tax at that time was done by local authorities.
and may be in local records offices,
I see you are in east sussex, this is a list of what they hold for that area

http://www.eastsussex.gov.uk/NR/rdonlyres/7E14653C-B147-4739-B997-5A424BD0C8EA/0/Vehicles.pdf

you might end up trawling through the registers looking for talbots...