I'm installing Gentoo on my P3 (I'm using a P4 here), but I don't know how to repartition everything. I'd like to delete the entire hard drive and start anew, but there isn't any /dev/hda (or any directories for that matter) around. What do I do?

(According the instructions in gentoo.org I'm booting using liveCD and I have a connection to the internet)