Details of all local clubs can be found in most libraries. Failing this, contact the Dog Warden who is employed by your local District Council for help in locating a suitable club near to you.
Your veterinary, pet shop windows and local newspapers are other sources of information.
Most obedience clubs accept all breeds and cross breeds but there are also breed specific clubs, such as branches of the British Association for German Shepherd Dogs which only accept dogs of a particular breed. If these clubs are of interest to you they are invariably registered with the Kennel Club who should be able to supply contact details.
I would always recommend that you watch your chosen club in action and have a talk with the trainers before you finally decide which club to join. Like all volunteer groups, some are very good and some are very poor. In most areas there should be a choice of nearby clubs.
Regrettably, there is no requirement for any club instructor to have attended any course or achieved any standard prior to either teaching at a club or advertising private dog training courses.
Some clubs do run training courses for their instructors or you may be lucky in that you find a club where one of the trainers holds a Kennel Club, British Institute of Professional Dog Trainers or similar qualification.
Do not be afraid to ask clubs what qualifications are held by their trainers. Beware of those whose reply is that, "all our trainers are most experienced", as they are avoiding the issue.