Soil and ferts combos for a new indoor grower

Im going to try to grow here in a couple of weeks and dont know what kind of soil and/or ferts to use. I want to try to go organic but only want to buy one soil and 1 or 2 ferts form start to finish. Does anyone know what will work? I only have 2 seeds and the 3 gallon pots. Im looking for something that is well .. cheap. Any help would help alot. I order stuff online also so web site are my best bet, but I also have a lowes near by. Thanks