Your steering wheel horn switch may be the problem, or that "clock spring" (as they call it) in your steering column may be the problem.
You need to find the horn relay and unplug it. Remove it from the MAIN fusebox in the engine compartment. It's next to the battery. Remove the lid. There should be a diagram on the inside of the lid.
If you do the easy/lazy way and just pull the wire off the horn, then you open the possibility of a new problem.
If your problem gets worse, it will have the horn relay stuck on (energized) all the time, and you'll find your battery "going dead" if you don't drive the car every day.
Look in your owner's manual to find where the horn relay is. But I'd get the problem repaired, because my horn didn't work once and a guy in a truck changed lanes into me and I couldn't warn him I was there or get out of his way, so he hit me. You really need your horn. For pedestrians too, just in case.
-General automotive mechanic since 1972