You can also ping the site through the command line (command.com in 9x / command or cmd in NT) and it will return the IP.
C:\>ping
www.anandtech.com
Pinging
www.anandtech.com [216.151.100.123] with 32 bytes of data:
Reply from 216.151.100.123: bytes=32 time=353ms TTL=239
Reply from 216.151.100.123: bytes=32 time=372ms TTL=239
Reply from 216.151.100.123: bytes=32 time=443ms TTL=239
Reply from 216.151.100.123: bytes=32 time=381ms TTL=239
Ping statistics for 216.151.100.123:
Packets: Sent = 4, Received = 4, Lost = 0 (0% loss),
Approximate round trip times in milli-seconds:
Minimum = 353ms, Maximum = 443ms, Average = 387ms
Violla, no 3rd party tools required.
DC