Brian's domain name expired and he can't access his website now. Leo says that if Brian paid someone to do his website and let them register it, chances are they own the website domain and not Brian. It's a very common practice. Sometimes, they can fall off the map leaving him unable to renew his domain.
Brian should find out what registry has the site, and there should be a process that will allow him to claim back the domain name. But Brian is on the clock. If he doesn't know what site registered the domain name, he can do a WHOIS search. There are a lot of companies that can do WHOIS searches, one of them is who.is. Then he can contact the registrar, and they have a process to claim it. If there's a GoDaddy ad on his page, it could be that GoDaddy did the registration.