While working on ALSA sound for my old PII Compaq Deskpro, so far so good, I came across this: In the Gentoo Linux ALSA Guide there is a sentence "Although you might have installed alsa-driver, alsa-libs and alsa-utils, only the first will have to be installed again, since it will put the alsa modules in /lib/modules/*/kernel/sound/pci/.". The name of the library package should be "alsa-lib".
Corrected. Thanks for reporting.