I buy on ebay and also First In Fragrance (Aus Liebe Zum Dufte). I've had excellent service from FiF. I'm also planning to try Les Senteurs. Its also worth going directly to some of the perfume houses for sample packs - depending of course, on whether you want to try enough from one house to make up a pack. Some excellent (and good value) ones are Maison Francis Kurkdjian, Parfum d'Empire and Andy Tauer.