I have a sub-domain site with paid hosting, if I buy a domain name through Bravenet can I use it for my existing site?
Also, If I buy a name for another site I am ready to build, what is the procedure? Do I have to wait for the registration before building the site? When will I know it's 'live' and ready to use?
Can anyone just outline what needs to be done after purchasing a name?
yes, you can use it with your existing site (you just have to move the files)
if you buy another domain for a site you are building you have to wait at MOST 48 hours(two days) before you can upload your site or see it
and once you buy the doamin you just wait (for two days tops) and after that upload your files if your doamin isn't ready them you have to give a support ticket