Linux has two sound systems, OSS ( Open Sound System ) and ALSA. Each has hardware they support. ALSA is the newer system, so try there first. You can go here for ALSA.
http://www.alsa-project.org/alsa-doc/
Sound cards are listed by card manufacturer, not the manufacturer of the system. To help here, open a konsole, and as root run the command 'lspci' and look through the output for what the card is recognized as. Then look for a driver for that card, or chip set.
Here is the link for OSS.
http://www.opensound.com/oss.html
Once you find the driver, you use the command 'modprobe' to load the driver. Install a mixer from your distros install CD's or through the internet. Make sure you are not muted, some distros mute the output by default.
