Paris horse racing Longchamps

I will vacationing in Paris in October and wanted to spend an afternoon at the track at Longchamps. the track website says take the Metro to Porte d'Auteuil and take a shuttle but the shuttle only runs on weekends. Any ideas on how to get there during the week? Are there cabs around Porte d'Auteuil Metro? This will be my first time in Paris so I am not that familiar with getting around.