I have a cheaper way and you don't have to go to the store if you keep some basic items on hand. Homemade dumplings are very simple to make and taste better than the store bought kind, hands down.
2 cups of flour, unsifted
1 tsp salt
1 tsp baking soda
3/4 to 1 cup of sour milk or buttermilk
Mix dry ingredients and add milk to make a soft dough that you can pat out on a floured board. Pinch or cut off small pieces and drop into a boiling pot of stock, soup or stew.
If you don't have sour or buttermilk, Check the Quick Cooking Tips and Substitutions Page