When I first moved to the San Francisco Bay Area 20 years ago, I had only been vegetarian for a few months, and was already exploring transitioning to a vegan diet. I visited a Whole Foods Market for the first time, and was overwhelmed with the number of choices. I piled my cart high with lots of ready-to-eat vegan meals, snacks, and desserts. Eating this way for years, while wavering between ovo-lacto and vegan, I gained weight and didn't learn much about cooking.
Nowadays, I do most of my grocery shopping in the bulk and produce sections. Bulk buying is especially helpful for me as I don't drive (so can only carry so much), and only have myself and boyziggy to feed. I can buy either a little or a lot of a food and still pay the same price per pound. And when Ziggy gets a City CarShare or ZipCar for grocery shopping, we can really go crazy in the bulk section.
Though we chose our current apartment partly because it was within a mile (walking distance) of a Whole Foods, our favorite place to shop is Rainbow Grocery, a local collective. Regardless, both stores have good bulk sections, as does the local chain Real Food Company. Prices vary, but Whole Foods occasionally has a sale on all bulk items, which is a great time to stock up.
Pictured is a good representation of the kinds of items we buy in bulk: Whole grains, flours, beans, nuts, dried fruit, dried herbs, and spices, all organic when possible. As you can see we have a motley collection of containers. We label our herb and spice containers with the date of purchase/refill so we don't end up with something rarely-used being 2-3 years old and flavorless by the time we cook with it. The other items we tend to go through much more quickly, to the point where I'm now considering looking into getting 25 pound bags of oats and rice and some large containers to store them in.
I'm happy I've made the transition not only to a vegan diet, but a diet rich in whole foods and home cooking. Bulk buying has been a real help in that regard.