info need regarding rtld internals

[Channa <channa.kad%gmail.com@localhost>]

Hi,
I am looking at the NetBSD source code for rtld implementation,
I have read many documentation but i am still not clear with how
kernel gives control to _start () and who fills the GOT entries.
My query goes like this:
Kernel gives control to ld.so and ld.so relocates itself before the
program exeuction
since ld.so is a shared library too. But meanwhile how the GOT entries
are filled and by whom?
Who fills the environment and argv , stack initialization ??
Could you please shared some documentation which gives me a clear idea
on how rltd works with kernel
and user programs??
Could anyone help me in understanding all the above queries.
Any document to be referred to understand the above would be helpful.
Thanks in Advance,
Channa