These natural nutrients are available at your high-end health stores and food markets. Make sure to buy the organic ones with no chemical fillers. Lower-end (cheaper) vitamins found in chain-type stores have too much junk added, and many times the ingredients aren't natural at all. Just read your labels.
Some of the quality vitamin supplements may be pricey, but when it comes to quality products, they are worth the extra buck.
Concerning your diabetes, return to a whole foods diet, particularly sugars only found naturally in foods, the pink packet to drop into your hot drinks or stevia found at the health market (just a pinch of either one), and water, water, water. Avoid chemical foods, fats and simple carbs. This will help. Then exercise and get plenty of rest. See if this makes an immediate difference.
You might want to do a hair test to see if you have other toxins at the root of your blood sugar issues. But know that detoxing and returning to a natural lifestyle will make a big difference, and put you back in control of this.