I need a domain for free? Or where GoDaddy gets their domains?

I need a site (.com, .net, .info, .us) but it needs to be an acutual domain, not yournamehere.tk or yournamehere.co.nr. I already have everything I need to run on it (mysql, apache, ubuntu, server, files (html, css, asp and php)). Anybody know where I can get a free domain?