Doing Business on the Internet is much the same as running a business in the brick and mortar world.
Your blog/website is comparable to a storefront, your email and RSS subscriber list(s) to a mailing list ... you need a product or service to sell, to know where to find prospects that want or need what you have to offer, and make it easy for them to find you, so that you can eventually convert a % of your prospect list into customers ... then repeat customers. You have to learn how to sell yourself, as well.
It demands research, learning, experimenting, testing, tracking, reacting, systems, structure, patience, persistence, consistency and focus.
I know that's true, because like everyone else that has ever managed to eventually make a full time living on the Net ... I started out back in 1996 part time, after working an 8 to 10 hour day at my 'real job, I put in another 4 to 6 hours a day, for years, until I was finally able to work full time Online ... but I did it.
And you can do it, too ... just stop chasing the next big thing, find something you're good at and enjoy doing, and focus on building and running your business.