Excellent post. My group of like-minded folks have food, water, shelter, heat and defense pretty much covered. The surrounding neighbors have plenty of animals including sheep for wool and are learning how to make clothes. The topic of bartering is also being discussed. However, there are many, many skills that are lacking. We are still very dependent on running out to Menards or Home Depot for replacement blades, tools, nails, etc.
Learning how to make biodiesel is my current research project. Lye, methanol and veggie oil. Now, how can I acquire these if TEOTW hits? Burn hardwood to make lye; construct a still to burn wood to make methanol, grow sunflowers to get the oil. How do I make a still when I can't run to Home Depot to get copper tubing? Yikes... so much to do.