LevelManager script used in my tutorial about Networking with Unity (in French @ http://www.demonixis.net/blog). It's used for spawing players in the level.

LevelManager.cs

using UnityEngine;
using System.Collections;

public class LevelManager : MonoBehaviour 
{
	public CameraFollow playerCam;
	public GameObject playerPrefab;
	public SpawnPoint[] spawnPoints;

	void Start () 
	{
		if (Network.isServer)
			SpawnPlayer();
		else
			Network.Connect(NetworkManager.GameToJoin);
	}
	
	void OnConnectedToServer()
	{
		Debug.Log ("Un nouveau joueur s'est connecté !");
		SpawnPlayer();
	}
	
	private void SpawnPlayer()
	{		
		int index = 0;
		
		if (NetworkManager.GameToJoin != null)
			index = NetworkManager.GameToJoin.connectedPlayers;
			
		Debug.Log (index);
	
		// Attention ici on utilise Network.Instanciate et pas Object.Instanciate.
		var player = Network.Instantiate(playerPrefab, spawnPoints[index].transform.position, spawnPoints[index].transform.rotation, 0) as GameObject;

		playerCam.transform.position = spawnPoints[index].transform.position - new Vector3(0, 0, -10);
		playerCam.transform.rotation = spawnPoints[index].transform.rotation;
		
		// Mise à jour du script de caméra
		playerCam.target = player.transform;
		playerCam.enabled = true;
	}
}