When traveling internationally, I used to pick up whatever currency I needed at the airport, until I discovered International Currency Express in Beverly Hills. Its rates are good and save me about 10%, compared to airport rates. The staff is also very knowledgeable and helpful. My friends now buy their currencies from them online, and it always arrives quickly and safely.
International Currency Express, 427 N. Camden Drive, Suite G; (310) 278-6628, http://www.foreignmoney.com