How do I find a listing for agents who represent UK film directors and
writers? The listing would need to contain some information about
their submissions policy and contact details, preferably named
individuals within the agency, e-mail and postal addresses.

Hello filmdog-ga,

The Directors Guild of Great Britain website has some helpful information.


Directors Guild of Great Britain
http://www.dggb.co.uk/


Directors Guild of Great Britain
Members Search 
http://cgi.guild.plus.com/cgi-bin/page.pl?page=mdbs


Click "Search" without entering a name to get a list of all of the
members.  Click on a member's name for more information.  The data
provided gives the name of an agency under "Contact".


Googlenut

Thanks, that's really useful information