http://office.microsoft.com/en-us/officelive/fx102390721033.aspx
Once signed up, here are the sites you’ll need to know. They don’t really tell you where to login to Windows Office Live Workspace:
Sign in to Windows Office Live at: http://www.officelive.com
Edit your Windows Live account at: http://login.live.com/
If you have a domain, you can DNS point it to Microsoft’s servers, but if you don’t Microsoft will give you one domain free. It’s pretty sweet deal. The free account can have up to 10 email accounts and it makes managing users easy. Compare it to Google Apps for Small Business.