1. Big Box Stores
2. Small Box Stores
3. Local and specialized nurseries
5. Plant/Garden shows and friends.
I've found plants through every one of these venues, so I can speak to each from personal experience, as well as dig up some intriguing, journalistic factoids for y'all. But first, any categories that I've missed? I'm not going to include collecting from the wilderness, of course, because so many useful and beautiful plants are disappearing from the wild, it's become a very complicated subject and way beyond the scope of this blog.