If your dad didn't leave a will then I believe his estate will be "in probate" and you will need some help to administer it. The probate helpline can help:
The Probate and Inheritance Tax Helpline is open Monday to Friday 9am – 5pm. The 0845 30 20 900 number offers callers the following 3 choices
1) Leave an order for forms and leaflets on the automated service
2) Speak to a Probate advisor
3) Speak to an Inheritance Tax advisor
But do yourself a favour and leave it until after the funeral - you have enough to deal with already.
Good luck to you.
Thank's for the links.
Dad only had about £3800, If I understand correctly, the estate has to £5000 or over for probate ?