Gentoo n00b help

[Apollo]

Hello,  I am new to Linux.  I have tried RedHat a few times but always get
frustrated with the RPM bullsh*t and give up.  I've seen several posts about
Gentoo and the emerge command so I decided to install Gentoo and give it a
try.
The install, configuration and almost everything else I've tried has worked
on the first try.  The only things holding me up are a couple of commands
which I need to run on start up.   I have to run these commands at the
prompt after the system starts.

ifconfig eth0 up
dhcpcd eth0

hdparm -X66 /dev/hdb

I've looked at the docs at Gentoo.com and searched the forums but I can't
find anything that tells me how to run these on startup.  If its too
complicated to explain here if anyone knows where I could find instructions
I'd really appreciate it.

Thanks
  Apollo