A New York Times article all about kombucha! I didn’t know about Kombucha Exchange, where you may be able to find someone to give you a starter culture. Here’s a recipe that’s close to what I ended up with after trying several alternatives.
Thanks to Dave Lull.
OT: I thought this might interest you:
https://kottke.org/10/03/high-fructose-corn-syrup-linked-to-obesity
There’s no need to “find someone to give you a starter culture”. You just pour in a bottle of whatever kombucha you’ve found you like from the grocery store. Likewise for yogurt.