I don't think that at the time the Vikings had enough to gain from sending ships to Vinland. They had the technology, just not the motivation really. Plus, I think they would have had a hard time with the Natives. Yes, the Vikings were more advanced technologically but the Indians were more numerous and knew the terrain, so in the long run, I think the Natives would win.
Also, if the Vikings were there for long enough, the Natives would probably adopt some European technologies. Now that would be interesting!