1 1/2 pounds small salad potatoes
3/4 cup plain fat-free yogurt
3 tablespoons white wine vinegar
1 tablespoon minced fresh dill
1 tablespoon minced fresh parsley
2 teaspoons minced fresh tarragon
1/2 medium onion, chopped
1 celery rib, chopped
1 small carrot, coarsely grated