Well first decide what your definition of organic means. For me it means no soluble chemical fertilizers. I'll make my own soil using a base organic soil and whole additives such as bone meal, kelp meal, compost, worm castings etc. But I also put some mineral content in there including Epsom salt, vermiculite, perlite, silica sand, locally obtained clay, green sand, rock ash, rock phosphate. These are essentially chemical components but not considered "harsh" soluble fertilizers.
You could probably get a high quality organic base soil such as fox farm or super soil and then add some compost, worm castings and perlite and you'd be doing pretty well for yourself. You could then fertilize with a balanced organic mix fertilizer such as Foxfarm Happy Frog or Espoma plant tone (add bone meal and kelp meal).
You may also consider the benefits of adding some molasses to your watering mix which helps to give sugars to your soil microbes.
Consider mixing your soil up in a batch 30 day before you plant and water it with some dilute molasses, kelp tea, or fish emulsion. Mix the soil on a regular basis.
I'd do lots of research and learn what kinds of soil amendments you think will be best for your plants. Remember best rule of organic growing is feed the soil not the plant.
The more you do it yourself without buying all sorts of crazy products the better off you are. I've seen some beautiful plants grown for very little cash.
