Different operating systems, desktop environments, and applications keep their sound files in different locations. I use this information when I need a sound effect or notification, preferring to use something I already have rather than reinvent the wheel.
- Linux 32 bit: /usr/lib/libreoffice/share/gallery/sounds/
- Linux 64 bit: /usr/lib64/libreoffice/share/gallery/sounds/
- Windows: %systemdrive$\Program Files\LibreOffice x.x\share\gallery\sounds\, where x.x is the version number
- System: /usr/share/sounds/
- Conforming applications: /usr/share/APPLICATION/sounds/
- Linux: /usr/share/skype/sounds/