Connecting To Local Server With Virtual Machines

How do you go about setting up virtual machines so that they can see sites hosted on the host machine?

I've got Virtual PC 2007 and the disk image that MS supply for testing IE6 on Vista machines and I'm having trouble accessing my local Apache server (set up with XAMPP). Until recently I was able to set the XP VM's LAN settings to use a proxy server with the IP address of the host machine, but I got migrated to ADSL2+ yesterday by my ISP and now that's no longer working.

To access my sites locally, I set up httpd.conf like this:

PHP Code:
<VirtualHost *:80>  DocumentRoot "C:PathToFolder"  ServerName siteName.local</VirtualHost><Directory "C:PathToFolder">    Options FollowSymLinks    AllowOverride None    Order allow,deny    Allow from all</Directory>

and then in Windows hosts file I add 127.0.0.1 siteName.local.

So what's the best way of getting the host and VMs to talk to each other?