Flights from several U.S. cities on sale to Munich, Germany for about $568 RT. Some cities and dates can be found as low as $491 RT but for best times/layovers, $568 is the price point.
Search Google Flights, then search dates in Priceline and Expedia for cheapest fare. For Delta flights, some cities are best to book through KLM/Air France (it'll be double on Delta site), others will be Priceline or Expedia.
Available Departure Cities: San Francisco, Los Angeles, San Diego, Denver, Jacksonville, Orlando, Washington, D.C./Baltimore, New York City, Nashville, Kansas City (additional cities may be available -- search your favorite outgoing airport!)
Dates: March - May, and Sept - Oct including OKTOBERFEST (Sept 22-Oct 7). Prost!
Airlines: Delta/KLM/Air France, British Airways
Sourced: Dolce Does Travel