Back in the old days, all you needed was to have a regular ad in one of the popular organ magazines and the concert arrangements would come to you (provided you were a good organist with proper education, of course).
Now the times have changed and you need something more. You need to become remarkable. How to achieve this? I have 3 suggestions for you:
1. Be yourself. Don't try to become somebody else. Look deep into your likes and dislikes, into your character, and make use of what is unique about yourself. Remember the story how George Gershwin met Maurice Ravel and said he wanted to study with him. Ravel reportedly told him "Why do you want to become a second-rate Ravel when you are already a first-rate Gershwin?"
2. Specialize. Be the best in the world in as smaller niche as possible. Then you will become indispensible. This applies to organ playing as well. Organ playing is a broad niche and if you specialize and excell in some smaller sub-niche of organ playing, then you will become an expert in that field. So when people will want to find an expert in this small area, they will go to you instead of somebody else.
3. Help other people grow. Even though you might not be an expert in organ playing yet, you certainly have your own experiences to share and stories to tell which will be helpful to other people.
A good way to help people is to regularly write a blog with a newsletter where you could share these things with your audience. This will help you to gather a certain amount of people who trust you and want to hear more from you.
Think about these tips and apply them in your life. With time, they will help you to become remarkable and different from other organists and the word about you will spread far and wide.
By the way, do you want to learn my special powerful techniques which help me to master any piece of organ music up to 10 times faster? If so, download my video Organ Practice Guide.