Where are you located at? I know that you are in the UK somewhere, but if you are at close to London, you should take advantate of being so close to a major publishing center. Meet with the publicists and editors - you can get yourself invited to industry parties and such. You mention seeing Mieville at a huge convention - how would you like to meet him in a more intimate setting and chat with him over beer, wine, or whatever drink you prefer? It can happen if you make it - check out Werthead (of the blog The Wertzone and an admin/moderator at several genre webpages). He goes to the Gollancz party often and then goes out drinking later with authors like Joe Abercrombie.