Instead of a wired connection via the cradle you can also access the network wireless. Under START, SETTINGS, CONNECTIONS you will find a utility to configure WLAN (WLAN Settings). The settings will be saved in a configuration file.
Alternatively you can use the Windows ® Zero Configuration. But it offers less options and the settings will not be saved to a configuration file.
The pre-installed NetSearch application displays detailed information about the WLAN connection. Among others you find the MAC of your IT-800 beneath "Physical address". Please make sure that WLAN power is enabled in order to use that utility.
From within your own application, you can call "GetAdaptersInfo" from Win32 API to get both IP and MAC address.