Registering a domain is the last step on the domain name process, most if not all web hosting companies provide domain name availability check services. After choosing your domain name, bear in mind that, there might have been someone with the same type of your domain name, in this case what will you do? well, there are always suggestions from the same web hosting companies whenever you search for your domain availability.
So, if your domain has already being in use by another website owner, you have options of choosing from the ones available and suggested by your web-hosting provider, else you have to think of another name.
It doesn't cost much to have a domain name, this also depends on your domain host provider. For more information on domain registration, contact us.