I came across sites with some new information, and programs I haven't heard of earlier (they test as clean when scanned with virustotal.com). All are in Russian, but even if you don't speak a word of the language, I believe it's readable - game titles, formats, program names and links are a universal language :)

http://www.ctpax-x.ru/index.php?goto=files
Some useful files, mostly "ToWAV" - a converter that seems to handle audio from many games that other programs won't extract

http://heimdallr.hut1.ru/MusGamePlayer.htm
Seems similar to the famous "Game Audio Player", but supports many newer games and/or formats.

http://gam-mus.narod.ru/
Guides to extracting dozens of game soundtracks, with formats each game uses and programs that can extract / convert the music.

Game Audio Player only supports 3 games?