Hi Lynda,
We have used several sources, but DFS in San Javier are to be recommended (don't be put off by the name, nothing to do with DFS UK!). English speaking and very helpful either at the shop or via email. For electrical goods we have used ELECTRO REGALOS in Roldan. This is a Spanish run shop but the staff speak very good English and, again, are very helpful. It's a large modern shop and also stocks wider items other than just electrical. We have bought lights, washing machine and garden table & chairs from them.
If you need directions maps etc, only to happy to help.
Dave&Pam