Every girl has here body issues and this can be a doozy. I've got a pretty prominent adam's apple myself. I think that, as with any physical flaw, you just have to do your best with it. With care, you can do pretty well, though.
Illusion and distraction can get you a long way with this. I hardly ever wear scarves, but I own a lot of turtlenecks. High neck tops are tricky in warm weather, but it can be done. I've even got a turtleneck halter top. I think turtleneck t-shirts are pretty cool, actually.
Wear long hair. That way you've got at least 3 directions covered. Wear clothes and accessories that call the eye away from the neck.
I find that I can push/pull in my apple to where it retreats mostly into my neck. To it I have to straighten my next a bit, but with practice it stays fairly well. It's kind of good posture thing. The only problem is it evidently protrudes at times. Still, with enough practice, I think you can train yourself to reposition it such as to minimize it considerably.
Lyric