This article is a work in progress.

$ sudo apt-get install dhcp3-server

  # /etc/default/dhcp3-server # This is not needed on Ubuntu 8.04 Hardy
  INTERFACES="eth0"

$ sudo nano -w /etc/dhcp*/dhcpd.conf

# dhcpd.conf for Helia labs
# Copyright 2006 Tero Karvinen http://www.iki.fi/karvinen/ubuntu_dhcp.html
# License: GNU General Public License, version 2 or later
# ChangeLog:
# 2006-03-27	Initial version, testing in Helia labs
# Don't set "authoritative" until everything else is correct in dhcpd.conf
authoritative;	# Warning: this overrides other DHCP servers
# Default options in Ubuntu:
ddns-update-style none;
default-lease-time 600;
max-lease-time 7200;
log-facility local7;
# Subnet row defines server's network card. Also set in "/etc/default/dhcp3-server"
# 'ifconfig' shows subnet (ipaddress, zeroes as in mask) and netmask
subnet 172.28.0.0 netmask 255.255.0.0 {
	host terotestaa {
		# 'ping target_host', 'arp' shows MAC address
		# only give DHCP information to this computer:
		hardware ethernet 00:0D:56:73:F0:0D;
		# Basic DHCP info (see 'ifconfig', 'route', 'cat /etc/resolv.conf')
		fixed-address 172.28.1.7;
		option subnet-mask 255.255.0.0;
		option routers 172.28.1.254;
		option domain-name-servers 172.28.1.67, 172.28.1.69;
		# Non-essential DHCP options
		option domain-name "tielab.helia.fi";
	}
}
# 'sudo /etc/init.d/dhcp3-server force-reload'
# http://www.iki.fi/karvinen/ubuntu_dhcp.html

 $ sudo /etc/init.d/dhcp3-server stop

Now that you have DHCP working, you could try Ubuntu PXE.