as said a local motor factor will
help you with the parts
replacing the pads is so easy even a stealer can do it, I must admit I have not done this job on a mk4 1.2 but normally one large bolt is removed so you can swing the caliper away and then slide the pads out
refitting is just the reverse but you will need to force the piston open to make room for the new (thicker pads), this is normally quite easy to do with a large screwdriver, hammer handle or somthing , just use it as a leaver and push the piston in
make sure you remove the lid of the brake fluid reservoir and you should see the fluid level go up as you push the piston back
once fitted take it easy on the brakes for 200 miles so they can bed in properly going too mad on them before they are worn in may warp your disks
should take a total novice no more than 2 hours and save yourself £50