Hello I am a lawyer of over 15 years experience I would suggest the following. Write to your solicitor telling him you want to make a formal complaint about his lack of response and failure to provide you with the information you require. All solicitor must have a complaints system and they have a duty to tell you about it at the outset. If you have your original letter of terms and conditions from your solicitor the complaints procedure will be set out there. You should write sayin you want to use thus system. If you do not have the letter then simply wrote to the solicitor asking for details of their complaints procedure and stating why you want to use it. By making this request you are forcing the solicitor to undertake quite a lot of paperwork. This may be enough to get the information you want. If not you can then make a complaint to the the Solicitors Regulation Authority. http://www.sra.org.uk/consumers/problems.page.
You could also sack your current solicitors and instruct another firm who might treat you in a more respectful and helpful manner. If you have legal aid then you can transfer this to another firm.
I hope this answer is helpful. The complaint can be email or in a written letter.