Hi Gwyneth. I reckon you'll find DIY stores all over the place. However, in the Las Chafiras area, there's one that I've visited on more than one occasion. It's a question of whether I can remember where it is!
I think this is the way from Golf del Sur. Come out of the Urbanization and join the road towards the motorway. When you get to the roundabout, take the first exit (the one before the motorway slip road). This DIY store (Chafiras) is eventually off this road, to your left (I think). It's a large store and you should be able to find what you need.
There's also another huge DIY store in the area, called Afortunadas and this is on the road running parallel to the motorway, which you would access from Golf del Sur by going nearly all the way round aforementioned roundabout (fourth exit). You'll see it on your left.
