Software that I've been using now and have had great luck with is called Technitium MAC Address Changer (TMAC). It's completely free and very easy to use. It is able to list every network adapter and list detailed information about each one. It also supports not only IPv4 but also IPv6. It provides a command line interface as well if the GUI isn't enough. This software meets all my requirements.
Technitium MAC Address Changer allows you to change (spoof) Media Access Control (MAC) Address of your Network Interface Card (NIC) instantly. It has a very simple user interface and provides ample information regarding each NIC in the machine. Every NIC has a MAC address hard coded in its circuit by the manufacturer. This hard coded MAC address is used by windows drivers to access Ethernet Network (LAN). This tool can set a new MAC address to your NIC, bypassing the original hard coded MAC address. Technitium MAC Address Changer is a must tool in every security professionals tool box.
