The music format of the original Nintendo Entertainment System is known as the NSF, and can be played with the Nosefart music player and Winamp plug-in. Music packages can be obtained from the archive at Zophar’s Domain.
The Super Nintendo featured some of the most popular game music ever created, using a sound processing unit which was quite possibly ahead of its time, the Sony SPC700. A range of players for Super Nintendo music are listed at zophar.net, with SNESamp possibly being the best plug-in for Winamp. Music packages are available from snesmusic.org and Zophar’s Domain.
The ZSNES and Snes9x Super Nintendo emulators include functions for dumping SPC sound data while playing games. Illegitimate use and distribution of commercial games is not condoned.
Development of a music format for the Nintendo 64 began in 2004 as an extension of the portable sound format and is based on the audio module of the Project64 emulator. Nintendo 64 music files are known as USFs, with players and soundtracks can be downloaded from USF Central.
Music from the original Game Boy series of games (before the Game Boy Advance) are stored as GBS files. A Winamp plug-in was being developed at meridian.overclocked.org before mysteriously disappearing – a modified version of release 0.3.1 and its source are available here. Game Boy music packages are archived at Zophar’s Domain.
For Game Boy Advance music, look for GSF sets, files based on the portable sound format. GSF soundtracks as well as a Winamp plug-in to play them are available from GSF Central.
PlayStation and PlayStation 2 music files are tagged as PSF and PSF2 respectively, and were the first music types supported by the portable sound format developed by Neill Corlett. PSF packages can be played with Highly Experimental, with soundtracks available from a number of mirrors.
Several popular games have official soundtrack CDs released, and many of these are catalogued at sites such as Chudah’s Corner and Video Game Music Database. Additionally, the Falcom CD Catalogue is dedicated to music distributed by Nihon Falcom and its Sound Team JDK, perhaps best known for their endless re-arrangements of music from the Ys series of games.
Unofficial arrangements are more commonly known as remixes. Some of the more popular video game remixing sites include OverClocked ReMix, VG Mix, Dwelling of Duels, and Remix: TS.
There are also a number of commercial game music concerts becoming increasingly popular outside of Japan (where game music culture is much more widespread), such as those held by Eminence Symphony, the Play! Symphony World Tour, and the Distant Worlds Final Fantasy concert series.