I do this, a local Academy advertised in the local press for supply teachers to join their supply pool of contacts. I see no reason you cannot contact themself anyway, try to find out who the cover manager is via their website or your details might get lost amongst general enquiries. Its worked out very well, work has been more regular and much better paid then agency work and registering was just as easy. As for payment I simply supplied my bank details and the money goes into my account as it would for any other employee there. You might need to have a CRB done by some one else though. Its a good idea and I fully recommend it for next September.