You can get your graphics drivers from here http://support.amd.com/en-us/download
You need to find out the make and model of your motherboard and download the drivers from the manufacturers web site. if you dont know then download cpuz that will give you the details of the motherboard or remove the side of your case and it should be printed on the main board. (Turn your machine off and unplug from the mains first).
All drivers are free from the manufacturers site, never pay for drivers.