organize.cs

 public List<FolderVm> GetFolderVms<TItemVm>(ObservableCollection<FolderVm> folders, ObservableCollection<TItemVm> potentialMatches) where TItemVm : IItemVm
{
    var matchingFolders = new List<FolderVm>();

    foreach (var folder in folders)
    {
        var directoryName = new DirectoryInfo(folder.Header).Name;

        var matchingWebsite = potentialMatches.FirstOrDefault(x => string.Equals(x.Header, directoryName, StringComparison.CurrentCultureIgnoreCase));

        if (matchingWebsite != null)
            matchingFolders.Add(folder);

        matchingFolders.AddRange(GetFolderVms(folder.Folders, potentialMatches));
    }

    return matchingFolders;
}

private void Organize(object obj)
{
    var moveActions = new Stack<KeyValuePair<string, Func<List<FolderVm>>>>();

    moveActions.Push(new KeyValuePair<string, Func<List<FolderVm>>>("MoveByCategory", () =>
    {
        return GetFolderVms(FoldersVm.Instance.Items, Categories);
    }));

    moveActions.Push(new KeyValuePair<string, Func<List<FolderVm>>>("MoveByStar", () =>
    {
        return GetFolderVms(FoldersVm.Instance.Items, Stars);
    }));

    moveActions.Push(new KeyValuePair<string, Func<List<FolderVm>>>("MoveByWebsite", () =>
    {
        return GetFolderVms(FoldersVm.Instance.Items, Websites);
    }));

    while (moveActions.Count > 0)
    {
        var moveAction = moveActions.Pop();

        var folders = moveAction.Value.Invoke();

        var folder = folders.FirstOrDefault();

        if (folder != null)
        {
            var newPath = System.IO.Path.Combine(folder.Header, Header) + System.IO.Path.GetExtension(Path);

            try
            {
                if (Path != newPath)
                {
                    FileSystem.MoveFile(Path, newPath, UIOption.AllDialogs);
                    Path = newPath;
                }
            }
            catch (Exception)
            {

            }

            break;
        }
    }
}