hi i have just ought a renault meganne 1.6 vvt 2004. no stereo code.help ?

hi i have just ought a renault meganne 1.6 vvt 2004. no stereo code.please help there is no manual when i bought this off the trader. is there also a way of installing a branded face-of which will allow the car digital screen and the stering wheel remote to control the stereo.