CrossHair script

i am adding a cross hair for my project and im not the best scripter so if someboday could make me a script for the crosshair and have it appear when you left click and when you let go of left click it dissapears please and thank you very much!!!!

Check this forum thread out - http://forum.unity3d.com/threads/28437-Crosshair

The Unity FPS Tutorial explains how to create one yourself -