I have had quite a lot of wild fermintation experiance as well as making sour dough bread. I use Wild Fermentation by Sandor Katz.
Try making your own starter, with any flour, and water. In a bowl or jar mix 2 cups each of water and flour. Un florinated water is best.
Stire it every day to introduce wild yeast, then cover with a breathable cloth. Keep it in a warm place and add water to keep flour coverd. Mold might grow on the sides, but simply scrape it off. In 3 to 4 days it will start bubbiling as yeast grows producing lactobacilli which brakes down gluten as well as preserves it. Ad a little flour to keep the yeast alive. If it does not get food it will die and insted of smelling sour and happy, will get putrid. From this you can make yummy sour pancakes with coconut butter, lemon juice and raw honey. Or you could use the starter for sour dough. if you do remember to feed your starter there are lots of good recipes on line. Another baking and soking tip would be to buy hole grains soke them then dry and grind, this abviously takes longer.
I wish you luck on your baking adventure