Unfortunately the SceneView class is not documented. If you use Microsoft Visual C# you have IntelliSense which gives you all you need. SceneView.sceneViews is an static ArrayList that contains all open SceneViews (keep in mind there can be more than one). SceneView inherits from EditorWindow so every SceneView have a Focus() function like Elliot said. To focus the first available SceneView do something like:

// JS
if (SceneView.sceneViews.Count > 0)
{
    var sceneView : SceneView = SceneView.sceneViews[0];
    sceneView.Focus();
}

// C#
if (SceneView.sceneViews.Count > 0)
{
    SceneView sceneView = (SceneView)SceneView.sceneViews[0];
    sceneView.Focus();
}

Use EditorWindow.Focus.