On the windows boxes edit the hosts file, it can be found:
Windows 95/98/Me c:\windows\hosts
Windows NT/2000/XP Pro c:\winnt\system32\drivers\etc\hosts
Windows XP Home c:\windows\system32\drivers\etc\hosts
Open it in notepad
Then add a line similar to this:
192.1.2.3 RandomName
Where 192.1.2.3 is the IP-Address you are typing in, and RandomName is whatever you want to access it by, so to access the above example
http://RandomName/