how can i fix astra-g 2002 locking and window fault?

came to my car one morning the electric windows did not work and i snapped my key in the barrell, i bought a new barrel/fob and key,(at a cost of £158+vat) had the key programed that works fine. had an auto electrician out but he could not sort the fob or the electric windows. he said there was a module that works both the locking and the windows? could any body tell me if this is right, and where the module is located on a 2002 astra 1.6 petrol. regards ian