First, there are different techniques used to identify spoofing via arp. Softwares can be implemented  but I will just give a quick info not going too deep. You know that arp works mainly on LAN to request and recognize the mac address and ip address of different host in the same network when sent with respect to the ip address. When an arp request is being sent, the distinct host replies with both the ip address and the MAC address in unicast(one to one) depends though. And all these contains packets that is packaged in a frame that is transmitted in the network. Thus, one solution is implementing Reverse path forwarding. In the place where I work, we make use of Fortigate firewall which perform this aspect of RPF. Fortigate is owned by Fortinet which tries as much to enhance network security on different enterprise. We make use of forti analyzer, forticlient in compliance with fortigate(on an end user computer). Our firewall blocks ip packets from reaching a destination if it does not belong to the routing domain and if its subnet is corresponding our network. Also, since arp is mainly used by switches, security measures can be taken in the area of the switch but that depends on the process you want to use. One is port security on the switch.