Here are a number of sites, resources that as an enthusiast, WW historian, serviceman or family member of the 9th Air Force you might enjoy and find relevant.
Army Air Corps Library and MuseumArmy Air Forces Of World War II Museum.
9th Air Force History
US National Archives
Air Force Historical Research Agency
Sons of Liberty Museum US Army, US Marines, US Navy, US Air Force. World War I, World War II, Korea, Vietnam History. Veteran's Military History.