I believe the dhcpd.conf files needs to be in the /etc/ directory.. try this:
then make sure the script calls the ghost conf file from the /etc/dhcp3 directory.. should work then!
cp /tmp/ghost_dhcpd.conf /etc/dhcp3/ghost_dhcpd.conf
*Note to developers. you may want to change this in the script itself to avoid further issues for people. To solve the above issue, line 41 & 42 of ghost_phisher.py might be changed to:
dhcp_config_file = "/etc/dhcp3/ghost_dhcpd.conf"
dhcp_pid_file = "/etc/dhcp3/ghost_dhcpd.pid"
Hope that helps!