There should be better ways, but this will do for the moment.
#!/bin/bash for ipadr in 192.168.0.{1..254} do ping -c 1 -w 1 $ipadr done arp -n | sort -n -t . -k 1,1 -k 2,2 -k 3,3 -k 4,4 | grep ether
% ./ping.sh 192.168.0.1 ether 00:0d:02:xx:xx:xx C eth0 192.168.0.193 ether 50:7e:5d:xx:xx:xx C eth0 192.168.0.196 ether c0:ff:d4:xx:xx:xx C eth0