I'm unaware of such a tool. I can't imagine something like that being up to date and accurate. Produce retail is market driven and it can change daily. If prices are you primary motivator the Asian shops in the Richmond are the way to go. I think #2 Clement is at @ 6th Ave. on Clement. Just walk the street. There are several options.
re: Brandon Nelson
Expensive but good fruit at Cal-Mart in Laurel Village.
Excellent selection and pretty good quality for its class at both Marina and Western Addition Safeways.
Real Food stores are usually pretty good for mostly organic. My personal favorite is Rainbow Grocery, a wonderful, unchic health food market on Folsom and freeway overpass (Division?).
I avoid Whole Foods because I resent its offering so many commercial products under the aura of a health food store logo/name. However, its produce is pretty good and v. price-y.
For Latin-American produce at excellent prices, 24th Street more or less between Potrero & Mission.
Stockton Street in Chinatown is a trip! As pointed out, Chinese markets also plentiful on Clement. However, the Sunset is another option, since there are so many reasonably priced and good Chinese restaurants in that area, I'd bet there are also some good produce markets along Irving, Noriega, Taraval,the major shopping streets. There's a very popular one at Irving/22nd Ave.
Actually that market at 22nd/Irving in the Sunset used to carry lots of middle eastern type foods (dried beans, nuts, spices, cheeses) and their produce was pretty good.
There are lots of Asian markets in the inner Richmond along Clement Street. And I'd second Fine's recommendations, we used to shop at alot of those when we were in the city.
I love being able to shop at different ethnic markets - lots of them in the city (and Berkeley too, I've found) - depending on what I want to cook.
Subsequent to commenting on this, I visited Real Food on Polk for the first time in a while and was amazed at its improvement: lots and lots of choices, elegantly displayed!
Parking can be a bear except just before 6 PM, but if you shop at Walgreens, newly opened virtually next door, I guess it's feasible to leave your car and make a quick stop at RF!