According to the CDC, "manufacturers have begun shipping flu vaccines for the 2013-2014 U.S. season. Between 135 million and 139 million doses of vaccine are being produced. While some vaccine will be available in August, ample supplies should be available by September and October. Everyone 6 months of age and older should get their yearly flu vaccine, ideally by October."
More information on the 2013-2014 season can be found at the CDC website.
Healthy Roads Media has produced a few short videos on the flu for this upcoming season. They include inactivated vaccine, the live (intranasal) vaccine, and reactions to the vaccine. There is even a mobile site. For more videos on additional types of vaccines go to the Healthy Roads webpage on immunization.