This is my favorite brine recipe. I got it from the Salmon University site. It's called Salmon Candy. It turns out perfect salmon every time as long as you don't over do it in the smoker.
4 cups brown sugar
1 cup salt
1 tablespoon garlic powder
1 tablespoon onion powder
1 tablespoon cayanne pepper
Mix everything together very well then rub a liberal amount onto each fillet and put in a sealable container for 24 hours. Turn and shake every now and then. Take it out, rinse it off, dry it off real good and put it in the smoker. Use woodchips of your choice. I like hickory and apple. Change the chips every 2-3 hours. Depending on thickness of your fillets and type of smoker you have check after 6 hours or so. Smaller fillets take about 6 hours, large fillets take up to 10. Good luck and congrats on your catch.