In Holland every company is registered in a big database, so when you start your own business and want to register your name and such they automatically check if the name doesn't already exist and if it does, they check if they do the same kinda work.
If the name is the same, but the one is a courier company and you wanted to start a CD store, then confusion is hardly possible and your allowed to use that name. If you also want to start a courier company than you're not allowed to use the same name, unless you've gotten permission from the company that's already registered with that name.
I'm sure they've got databases like that in every country.