You can buy the soundtrack here:
http://warthunder.com/en/soundtrack

Some songs, including the legacy main theme, aren’t available for purchase, so you can get them for free here:
https://www.mediafire.com/?fadgeteb22...

Replace "tube" in the URL with "repeat" to have the music repeat =D
What's your Favorite? Vote Here: http://www.strawpoll.me/11825297