For an automatic car, the neutral safety switch is mounted on the firewall, near the brake booster (LHD). It is a small brown box, about the size of a deck of playing cards. There should be a cable running up from the shift mechanism that controls the lever arm on the switch. You can pop off the cable end and then try the lever arm in a different position, or move it slightly to see if it makes a difference.
If you have a manual there is a switch, but I do not know the location or operation for that, there were several recent posts on that, try the search.
Is the battery alright? The clicking noise could be a symptom of that.