A quick walk-through of installation of Xen 3.02 on Debian Etch (AMD64):
KERNELS=”linux-2.6-xen0 linux-2.6-xenU” make -j7 world
make install
make linux-2.6-xen0-config CONFIGMODE=menuconfig
make -j7 linux-2.6-xen0-build
make linux-2.6-xen0-install
make linux-2.6-xenU-config CONFIGMODE=menuconfig
make -j7 linux-2.6-xenU-build
make linux-2.6-xenU-install
vim /boot/grub/menu.lst
title Xen 3.0.2 / Debian GNU/Linux, kernel 2.6.16
root (hd0,0)
kernel /xen.gz dom0_mem=131072
module /vmlinuz-2.6-xen0 root=/dev/sda2 ro console=tty0
savedefault
Install xen-tools, xen-shell etc
update-rc.d xend defaults 20 21
update-rc.d xendomains defaults 21 20