All the places mentioned by the other posters are definitely good. However, for the true LA unique shopping experience you need to hit Fred Segal. They have 2 locations: 1 in Santa Monica by the Promenade shopping area and the other in West Hollywood on Melrose. I prefer the one in Santa Monica. Fred Segal is a great place to go if you want to see where and how the stars shop. Be prepared to spend a few bucks, but the selections and the setup are really good there.