I have my own soccer team, how do i register it to a league?

I have my own soccer team of 15 players, the name is "Carrollton Sharks". Now we have been praciticing for months and have seen through time that we are very good. I am the coach (even though im 15) but sometimes i hire other proffesional coaches with a liscense to coach to come and coach us and i pay him 80 dollars, we can only do this twice a month because it is so expensive, only 6 of us have our uniforms since they are expensive as well but will soon have our full team dressed with their uniforms to represent our team. Now that we have been practicing, we want to take the next step, register to a league but we dont know which one and we're trying to find one that isnt so expensive. Please help, Thanks!