[Asinkrit]

Код:

procedure TForm1.Button1Click(Sender: TObject);
var
  i:integer;
begin
  with treeview1 do
    for i := 0 to pred(items.count) do
      if items[i].Text = Edit1.Text then 
        begin
        SelectedItem := items[i];
        break;
        end;
end;