The closing date for the annual Machinima Expo is in a couple of weeks, though it might be extended.
http://www.machinima-expo.com/
It would be great to see some flight sim movies featured. Note that if any copyright music is used then the movie can only be selected as a screener. To win any awards, the music must not infringe copyright.
There are several places you can get free or creative commons music, for example
www.jamendo.com