Julia, what a great question

I've got to admit I didn't do much research - my business plan was and has continued to be very informal - more an ever-evolving notebook of thoughts on business goals, philosophy, and policy, etc.
That's not to say that a more thorough plan isn't a great way to go - I just found that for my purposes (I was not applying for small business loans or investors, etc.) a less formal setup works well.
Now I do recommend reading Google news alerts for specific industries you're interested in to see what the headliners are doing, what business is like for people operating in those sectors, what their pain points are, and to learn more about how you might better position yourself to approach these people with partnership info. Other than that, I'm wondering if anyone else has further suggestions or input on this?