Star Alliance airlines Lufthansa, SWISS and United are offering very good deal from Germany to Califronia. Return flights between Dusseldorf and Los Angeles are available already for €277. This is including all charges and fees. There is one short layover in Frankfurt, Zurich or New York depends on the routing you choose. At this moment plenty of travel options to sunny California are available in upcoming winter season 2016/2017..
Promotional sale with Lufthansa / SWISS and United is valid for flights departing from Germany to Los Angeles till 6th of April or 24th of April till 18th of May 2017. Max stay 3 months.
Booking sample
To book your accommodation in Los Angeles in advance you may use Booking.com.
Booking sample of cheap Star Alliance flights from Dusseldorf to Los Angeles from €277 here. In this case you will be departing from Germany to California on 13th of March. Your return flight from North America back to Europe would be on 22nd of March 2017.