One of the best income streams you can develop online is your own digital information products. If this concept intimidates you, it shouldn't. All it boils down to is organizing and sharing information and advice.
Don't let your fear prevent you from being a content developer. You aren't required to have certain credentials, a publisher or agent. This is just you passing along quality information to your reader.
Why do people buy info products over print books? There are a number of reasons - convenience, prominence in the marketplace (when they search for a certain keyword phrase, your product comes up), and the fact that most consumers buy a variety of books and courses when there's a topic they want to know - they usually don't just buy one.
Go ahead and go through the process at least once. It's not nearly as scary as you might think, and it will create a certain amount of authority for you as you begin to earn an online income.