Car's not even trying to start.

My car will not start ,a problem for my spring break. It doesn't even turn over or click or anything. It has done this before but it started up eventually, and now it won't. I pretty sure i'll have to go buy a new starter, but i have noticed a pattern. Both times it didn't start i put it into neutral without it started, a lucky thing or a cause? I think this because the automatic shifter plastic part that tells you what gear you are in ,with the yellow dot, is broken. By that i mean it won't show what gear you are in anymore. And i thought that there may be a sensor in there somewhere that thinks it is still in gear and as a safety feature will not let it start. I am tearing the center piece apart now to see if i can see such a thing. Is there a sensor in the shifter or somewhere else that could cause this, or do i get to go shoping for a new starter, can someone help me...

could be a faulty range sensor on the trans. its under the shifter easy to replace but the trick is getting it lined up so it will start in "P" & "N"

So do i have to buy sensor if this is the problem or can i rig something, also where could i get one if i had to? ->Thanks