Don't even think about phoning! If you do get through, you'll be talking to the most rude, arrogant, unhelpful people who ever manned a 'helpline'. I assume you are here now with indefinite leave to remain. You can now apply for naturalisation, which will entitle you to apply for British passport. If you think getting information was frustrating, wait until you actually apply. You will be charged �214 for the 'service', for which you will be left in a queue for months (my spouse has been waiting for over a year now and even a letter from our MP has yet to yield results), you letters will be ignored and any phone enquiries will be treated with contempt. And at the end of it all, you will now have to undergo Blunkett's new pathetic and insulting 'citizenship ceremony'. Application forms and other details on this page:
http://www.ind.homeoffice.gov.uk/default.asp?pagei
d=16