Information about /etc/host.conf

[Xan]

Hi,

I searched information (and I not found) about the structure of 
/etc/host.conf, /etc/hosts and /etc/resolv.conf

I know that the structure of host.conf determines the order in which 
system resolves the domain names, and /etc/hosts and /etc/resolv.conf 
are the configurations about the hosts file and the dns resolvers.

But the info I want is:
1) How it works. What are the processes that system follows for doing 
that, before accessing host.conf and after
2) What are the packages that provide these files, and overall 
/etc/hosts.conf
3) How we can extend this system, for example putting another service 
(like NIS or other) (what are the files that we have to touch and what 
requeriments we have)

I need this info because I want to know more deeply the structure of the 
network resolution in *nix enviroments.

Can you explain me or pointing me some references?

Thanks in advance,
Xan.

PS: I know perhaps this is not the ideal place for asking but I ask here 
because the other information roads go to nothing