Online food shopping falls into two major categories: Raw materials and finished products. Do you buy either online? In the case of raw materials, many people have taken to buying in bulk from Amazon, especially if their order qualifies for free shipping and no sales tax. This can present a big savings, with an even deeper savings if you tack on their additional 15% discount for products that are a part of their subscription plan.
Not all items can or should be purchased from Amazon, but things like tea, olive oil, and pasta can be had for substantial savings. Amazon is also really helpful for people who don't live in or near a major metropolis and therefore don't have access to some more obscure ingredients or brands. But even New York chefs use Amazon as a source: Emma did a post recently on how Momofuku pastry chef Christina Tosi sources many of her ingredients from Amazon.
Foodzie and Guilt Taste are two sites that offer (mostly) finished products: jams, chocolates, cured meats, cheese, olive oils, etc. Gilt Taste does carry ingredients but they're focused more on high end, speciality items. You can also partake in subscription programs where boxes of offerings will be shipped to your home on a regular basis. Williams-Sonoma also has been offering this kind of selection for years, starting with their catalog and now online.
Finally, shopping sites like OpenSky and Fab offer daily deals to people who sign up to their site. OpenSky takes things one step further by having well-known chefs and cookbook authors select their favorite items to be offered. The idea is for the consumer to 'follow' a buyer who presumably offer things the consumer is apt to enjoy. Dorie Greenspan, Rick Bayless, Michael Ruhlman and even Martha Stewart are all OpenSky 'curators.'
Do you use these sites to purchase food? What has been your experience?