control own domain/zonefile ?

[Steve K.]

Ok, say I register foo.com, and I have my own linux box with bind 
installed, and I want to use that to control my own domain, instead of 
using zoneedit.com or whatever DNS applet a registrar might provide. In 
other words, I can setup a zonefile easily enough, but that only works 
so long as one manually points nslookup or dig to said linux box.

How do I make it world accessible, so to speak? I know I can change the 
name servers for the domain via the registrar control panel? Is this all 
there is to it? I get the feeling there is more. And what if the 
registrar doesn't have such an applet?

P.S.
I doubt this is possible, but is there any way to manually "register" a 
domain myself withotu going through one of those registrars? I mean, 
most cost only $10 USD, which makes me think that it doesn't really cost 
them anything, thus making profit on all those $10 registrations. 
Basically, eliminate the middle man. I mean, how EXACTLY does a 
registrar register the domain you pick via their website?

I also want to be able to control reverse dns (PTR records) which 
normally one cannot when using a registrars.

I know there are "ROOT" name servers out there that control all the 
TLDs, and so I figure there must be a way to directly register a domain 
in the area before the TLDs, or how ever the registrars do it.


Sorry, I know, I'm asking a lot of questions, but after doing a lot of 
searching, I can't really find much clarity on the matter, and maybe 
someone can really clear this all up for me I hope.

Thank you.