The electoral roll service can be accessed at http://webservices.data-8.co.uk/NameAppend.asmx or you may prefer the WSDL
The following methods are available:
ConfirmResidency
Checks if a person can be verified as living at an address.
FindResidents
Retrieves the names of any people who can be found to be living at an address.
FindYearOfBirth
Retrieves the year of birth of an individual.