help accessing set actuators

any clue on why this code doesn’t work? I have been scouring the web and trial-and-erroring (yes, that’s a verb now) for several days over this. It must be a newbie mistake, but i cant seem to crack it. Here are the relevant snippets.

                   ***the class where the property field is declared***

public class mouseOver : MonoBehaviour {
	private GameObject target; 
	public GameObject Target{

		set{StartCoroutine (setTarget()) //waits for the player to click to return target
			target = value; 
		   }		    
	}
	IEnumerator setTarget(){
		Ray ray = Camera.main.ScreenPointToRay( Input.mousePosition );
		RaycastHit hit;
		Physics.Raycast( ray, out hit, 100 );
		target = hit.transform.gameObject;
		if (Input.GetButtonDown ("rightClick"))  //need cancel with OnMouseDown? 
						yield break;
		if (Input.GetButtonDown ("cancelAction")) {
			            target = null;
						yield break;
				        }
		yield return null;
	}

                                       ***the class that calls set***

using UnityEngine;
using System.Collections;

public class magnet : MonoBehaviour {
	mouseOver m = new mouseOver();

	private void selectTarget{
		Debug.log(m.Target);  ///error, set or get accessor expected. 
		return null; 

	}

}

You cant use new for class which inherits from monobehavior.
Debug expects a string type.
You have return null; from void method. If you want force return, just return;

mouseOver.Target has no get accesor. Here is code to fix that error. Note there are plenty of other errors in the script once this one is fixed, as pointer out by @YoungDeveloper

 private GameObject target; 
 public GameObject Target{
     get {
         return target;
     }
     set{
         StartCoroutine (setTarget());
         target = value; 
     }            
 }

It will also save you a lot of hassle if you use convention in naming. Classes begin with a UpperCaseLetter. Variables begin with a lowerCaseLetter.