Raycast Collision-Detection

I have this set up so using the left mouse button fires a raycast from the camera. I have no idea how to check for collision with the raycast and a gameobject. I've looked everywhere, And I'm completely lost.

function Update () {

if (Input.GetButtonDown("Fire1")) {

var tbbeam : Ray = Camera.main.ViewportPointToRay (Vector3(0.5,0.5,0));   
    var hit : RaycastHit;
    Physics.Raycast (tbbeam, hit);
    if(RaycastHit.point(Vector3(0,0,0))){
        Debug.Log("Hit.");
    }

Debug.DrawRay (tbbeam.origin, tbbeam.direction * 10, Color.white);
}

}

P.S., I am a beginner. PLEASE HELP ME. I'VE BEEN GRUELING OVER THIS FOR HOURS.

This link might help you out: http://forum.unity3d.com/threads/15802-Plane.Raycast-Example