>>287
やってみてないけど、マニュアルにfbx読み込んでるの見つけた。Resources.LoadAssetAtPath

using UnityEngine;
using System.Collections;

public class example : MonoBehaviour {
　public GameObject prefab;
　void Start() {
　　prefab = Resources.LoadAssetAtPath("Assets/Artwork/mymodel.fbx", typeof(GameObject));
　}
}