2 Answers

Any one of these, check with your local authority.

http://en.wikipedia.org/wiki/List_of_prisons_in_the_United_Kingdom

Instructions
1
Contact the Prisoner Location Service, which is part of the UK prison service. You can either write, fax or send an email. The address and fax number can be found on the prison service website (see Resources).

2
Include the following information in your letter or email: the full name of the person you want to contact, any other names he or she is known by, date of birth and the reason you are getting in touch.

3
If the person you are looking for is in prison in the UK, the location service will pass your message to the prisoner.

4
The prisoner will be asked to give consent for his whereabouts to be released to you. If he gives consent, you will be given details of their location.

5
If you are the victim of a crime and want to locate a prisoner without going though these steps, contact the National Prison Service Victim Helpline at 0845 7585 112.

Resources 

• Read this Article in Spanish


• UK Prison Service


• Prisoners' families support group


• Victim support group

Read more: How to Find Someone in a UK Prison | eHow http://www.ehow.com/how_4926599_someone-uk-prison.html#ixzz2SpR6vV4y