You could try lsmod, that would list the modules loaded by the kernel, that certainly works on the Gentoo live CDs. For example my SATA chipset uses sata_sil which shows up when boot off a live CD. When I built the kernel for the machine I compiled the sata_sil driver in (not as a module!) and that was it.

Mark's right, if you're at all unsure of what you're doing then Gentoo probably isn't for you. I started with SuSE and only progressed to Gentoo once I knew a bit more about Linux. Ubuntu seems to be really popular, I've read a lot of good stuff about it.