My eye won't track to my bone on a certain axis? When I added an object constraint to my eye mesh, I selected my armature as my target and my bone as the one that I want my eye to track to, but it's not working.

Here's what it looks like:

And every time I move my bone, the eye doesn't track to it. That's mainly because that if you look right below the Head/Tail bar, you'll see an axis selection where the eye wants to focus the bone on a certain axis. For whatever reason, it'll track the bone when I select the X and X-, Y and Y-, but not Z and Z-, and that's where I want it to be because it'll place it on the original position it was in. Is there a way to fix this?
Actually your case is very simple, keep everything as is, use world space in the Track To constraint for both, the only thing you need to change is the (To: -Y) in the Track constraint. Which is the Y axis for the Bone.
Aside from that, you have some issues in the file, you have 4 armatures, each has bones, and all of them have default names, my advise is that you rename your bones, delete unused armature, this will make your work much easier, I also had to move the origin of the eye to it's bottom rather than the center so it doesn't detach from it's joint when rotates.Here's the .blend file: