There are some good deals to Los Angeles departing from Düsseldorf (Germany). Fly direct on Airberlin from 425€. Even Christmas and NYE!
I see availability mainly between November and February. To find the best deal I’d recommend to use flexible dates option on airberlin.com and look for ~490€. Next you can take these dates an book through online travel agencies.
Prices from other german cities are somewhat higher. E.g. Berlin to Los Angeles from 451 € when connecting through Düsseldorf.
Düsseldorf-Los Angeles: DUS-LAX 425€
Düsseldorf-Los Angeles (Christmas and NYE): DUS-LAX 425€
Berlin-Los Angeles: TXL-LAX 451€
Berlin-Los Angeles (Christmas and NYE): TXL-LAX 480€