Being good is good, but the exposure isn't going to just come beating down your door.
There are two reasons for this. 1) There's a good chance that many people are better than you. 2) You're as good at what you do as anyone else -- and that's the problem.

The world is a big, crowded space. And any space you're in -- and doing well in -- will become crowded very quickly, if it isn't already. Just being good does not entitle you to attention, victory, or spoils. There is too much to choose from, too much "fat" to cut through for people simply discover you.

You have to go out and make the sales. Oh, you're not a salesperson? Of course you are. You just may not be a good one.
Selling yourself is simple: Present a product, service or idea. Explain its virtues (i.e., what's great about it/you). Ask the person you're talking to if they feel your product is worth the value you've placed on it.

There's no course you need to take to be able to sell yourself. You just need to present yourself in a way that other people see what you see. Do you see value in yourself? Good! Now take the same ideas that you see in yourself and tell people about it. It really is that simple.

You're not selling yourself because you're waiting for someone else to see the value in you that you're not expressing. You have to be willing to put yourself out there to get the rewards.