I found out about permaculture when a gardening video on youtube had a video suggestion on forest gardens by Geoff Lawton. I was intrigued and started searching for more info on Geoff. That lead to several interviews Geoff did on The Survival Podcast. I then read Permaculture A Designers Manual, The Resilient Farm and Homestead, Edible Forest Gardens volume 1.
I am currently Read Edible Forest Gardens volume 2 and taking an online PDC at PermaEthos.