Best conch fritters,imho, are at Vie's on the East End. I've heard that Cap's across from the Post Office and a local place also have good fritters. The best salad used to be at the restaurant in Mongoose Junction. Since it has closed I haven't seen it on any menus. You might try the deli there and see if they have it.

Vie's are great! In Cruz Bay, I'd say Woody's has the best fritters.

Not a conch head myself, but do like to get some local food when on STJ. For dinner we like Sogo's. We ate at Sosa's last year and like that place, too. Hercules, across from the Lumberyard, has really good pate. And there are a couple of good cart/stand/trucks around the pavilion and post office. There are also a couple of small operations at the intersection in Coral Bay that put out good food. For a very local experience, have a drink at Mooie's in Cruz Bay or the Sputnik bar in Coral Bay (the bar itself, not the restaurant next door). Sweet Plantains is trying to put out asomewhat upscale West Indian menu.