Yes, there are cheap flight options that exist between Melbourne and Seattle. Getting cheap tickets to Seattle is especially possible if you are buying tickets in good numbers such as when you are traveling a group of people to Seattle.

http://www.cheapflightsservice.com/North_America/USA/Washington/Seattle/Cheap_Flights_to_Seattle_Airline_Tickets

Additionally, if you are booking the air tickets well in advance, then also the chances are there that the airline companies will be able to give you special money off on airfares. This is possible because the companies get sufficient time to accommodate such prices when you book them ahead of time.

Another good way of getting or booking cheap tickets is to make bookings on lean days as these days are considered to be one of the best days to make bookings. There are especially great deals floated by many airline companies if you book air tickets on some of the select weekdays such as Tuesdays, Wednesdays and Saturdays. Thus, you can definitely save a lot of money which can help you save some money for enjoying your trip at Seattle.