The official database is the PAF database controlled by the Royal Mail. But it costs quite a bit of money - http://www.royalmail.com/marketing-...dress-data-products/postcode-address-file-paf
This stackoverflow question asks about PAF alternatives. The question focuses on post codes but it might put you on the right path - http://stackoverflow.com/questions/...-paf-address-finder-via-postcode-alternatives
This stackoverflow question asks about PAF alternatives. The question focuses on post codes but it might put you on the right path - http://stackoverflow.com/questions/...-paf-address-finder-via-postcode-alternatives