Start IE or any other networking app, and using that given name will get you straight to your Mac's IP interface, ie.

Add a line containing your Mac's IP from above, and a name of your liking. (That probably depends on the version of Windows that you're using mine is under C:WINDOWSsystem32etcdrivers).

Start the Windows VM and edit the hosts file. I've set the Mac to use 10.211.55.5, for example. Open the OS X network preferences, choose the Parallels NAT adapter and set it to 'DHCP with manual address.' Use any adress from the free ones above, but not the '1'. Make sure the network mask is set to 255.255.255.0 For instance, I've used 10.211.55.10 - 10.211.55.254 for DHCP, leaving the numbers from 1 to 9 untouched. Open Parallels preferences, go to the Network tab, and make sure that the IP range entered for shared networking leaves out some numbers.

That way IE running on Windows can easily find the right server to connect to. However, it's better to set this to 'DHCP with manual address' on OS X, choosing an IP address from the network that you've assigned to NAT in the Parallels application. It provides DHCP services to the virtual machine, but the Mac side of it gets a dynamic address as well. Parallels comes with a network driver that adds two network interfaces, with one of them being used for shared networking. I've had trouble trying to correctly address the server running on OS X from within a Windows app, until I found this way to ease my life. Most of the time, I have those sites running locally on my Mac, using either Apache or Tomcat on OSX. I regularly use Parallels to test web sites on IE 6.

Parallels shared network mac address