http://wiki.archlinux.org/index.php/ModaliasPrimer
for example with my wireless card:
lspci | grep Wireless
01:04.0 Network controller: Intel Corporation PRO/Wireless 2200BG Network Connection (rev 05)
cat /devices/pci0000:00/0000:00:1e.0/0000:01:04.0/modalias
pci:v00008086d00004220sv0000103Csd000012F6bc02sc80i00
grep pci:v00008086d00004220sv /lib/modules/`uname -r`/modules.alias
alias pci:v00008086d00004220sv*sd*bc*sc*i*
ipw2200
The corresponding driver is ipw2200
Sometimes such automatic detection doesn't work.