Zero Waste Shopping
This can mean several things: buying articles designed to last eg good quality T shirts that last for years rather than cheap ones that lose their shape after a couple of washes, buying secondhand from charity shops, Ebay etc or getting stuff from Freecycle, Freegle etc, and repairing or repurposing items.
It can also mean using your own containers to buy unpackaged groceries. Shops like As Nature Intended offer the opportunity to refill washing up liquid and laundry liquid bottles, and many Lush products are unpackaged.
As for food, loose fruit and veg are of course easily available from all kinds of shops, but it isn't all that easy to buy other kinds of products. However, there are a number of places where you can do just that. The Zero Waster has a comprehensive list of these, as well as much other useful information about avoiding waste. See above for website.
The Source Bulk Foods has just opened in Chiswick, at 24 Turnham Green Terrace. They have a range of about 450 products, including flour, rice, cereals, honey, oil, and vinegar as well as cleaning and personal care products. You can buy whatever quantity you need and fill your own containers. Have a look next time you are in the area.