The following organisations can provide you with free advice. They are all free, confidential and non-judgemental:
National Debtline - a charity specialising in money advice and debt. There is lots of information on dealing with debts that is tailored to students and a confidential helpline to speak to a fully trained adviser. The service is free and non-judgemental.
StepChange - another debt advice charity that has information specifically for students, they are a charity that has expertise in managing money and debt advice. Again they are confidential, impartial and free.
Citizens Advice - CAB has a wealth of information on debt on their website. There are also local offices that can help with face to face advice, use the post code checker to see which one is closest to you.
Money Advice Service - another organisation that gives free money and debt advice. The Money Advice Service is part of the Money and Pensions Service.