For white and grey goods, try Jumbos electrical section in the Forum Algarve shopping centre. There is also a Casa store there which has a nice selection of crockery. Or if you are fortunate enough to have a makro card pop down there for everything you need!

Try Conforama at Guia (Algarve Shopping) or best bet is Moviflor in Olhao which is not far from tavira. If you are into IKEA pop down to Seville for the nearest store. Good Luck as I did the same before all these stores opened and I had to hare back and forward along the algarve for weeks.

P.S. If you need bed linen buy it in the UK (Dunelm) as it's all shapes and sizes out here.