Web-Sites of Athletic Organisations

For Higher-Level Competition / Governance:

Midland Counties Athletic Association Midland Counties AA . The Avon AA clubs come under the Midlands and South-West region of England Athletics.
England Athletics England Athletics The organisation which controls the three areas and nine regions organising athletics within England.
British Athletics British Athletics is the consumer brand of the governing body “UK Athletics”. UKA is the Member Federation of the IAAF responsible for athletics in the United Kingdom.

Higher-Level Competition (for some):

English Schools Athletic Association English Schools Athletic Association. The replacement ESAA site is now here, and looking good.
British Masters Athletic Federation British Masters Athletics Federation If you've reached the age of 35 ... you now become a "Master" not a Veteran (although you're still welcome to compete in mainstream competition).