I thought I should mention the new Supermarket in Candolim, Newtons.
I realise that it might be tempting to see it as a great place to stock up on a lot of things, and naturally thinking that, like the UK, they will be better value than small shops, but a word of warning... this shop is VERY expensive and their customer service leaves a great deal to be desired.
The shop is targeting tourists, and prices on everything are higher than the locals' shops.
British newspapers are at least 2 days old (with a stack on even older ones) and cost up to 50 rupees more than the Hira store, who get the previous day's papers at 4.30pm each day (and soon plan to get them the morning after printing). Hira is the only shop in town which gets the previous day's papers.
In addition, Newtons demand that you leave your bags with a guard outside the shop, clearly stating that they don't strust anyone (though I can't imagine shoplifting is a serious problem amongst tourists).... AND they have a sign up saying that you should remove valuables from your bag before handing it over (so also saying the guard can't be trusted with your stuff). When I went in, I had to walk round with an armful of valuables!
I was really angry that they expected my business and then made such demands... as though they were doing ME a favour.
You can get all the things you need at the small shops, at lower prices and without being treated like a criminal.