I'm not familiar with Virgin Media email, but you'd need to check on their site or with their support whether they use IMAP or POP3 for email. If it's POP3, then the Microsoft Mail app that comes with Windows won't work and you'll need to use a different email client app, or use Virgin Media's web mail access if they have one. If Virgin Media mail supports IMAP, then you should be able to step through the Windows 8 mail app configuration to set it up, perhaps with a little info from Virgin Media.
yeah, if you want to use the Windows 8 email app with POP, then you need to use the workaround:
create an outlook.com account (or google or yahoo, but yahoo, you have to pay for POP support the last time I checked). send your pop mail (to outlook.com). then add the outlook.com account to the Windows 8 email app. voila. all your virgin media email to the Windows 8 email app. Yeah, it sucks to use a workaround but if you want to use that app...
Yes, as dirtyvu said, as a work-around, you can use another service to forward to which supports IMAP. But it can be just about any email service that supports IMAP, not just outlook.com. For example, gmail.com would also work.