[x0x0]

Walling's book start small, stay small may help you get started. Amy Hoy talks about this a bunch; she runs a paid course but also has a ton of free content. You should check them out.

I've also read about people making serious money from advertising; it seems like the time investment to understand all that stuff is big enough that it could help you understand a small business instead.

[johnward]

I've gone through 30x500 which is kind of what shifted my focus to products. I haven't really taken any action with that yet though but it seems to work for some others.