As the wife of a British Citizen with a spouse visa in your passport you have the right to work - NO FURTHER PERMISSION REQUIRED
When you get a job the employer will "register" you for a National Insurance Number - this takes a few weeks to come through and you need to attend an interview
My wife has been trying to get a job but so far it seems that the employers are reluctant to take her on becasue she does not have an NI number
we will keep trying