iptables / firewall query

["Aseem Khurana" <aseemk netsoftglobal com>]

Our Linux Admin is out for a week, my running server has gown down, a
standby server has rhl.9, apache, php, mysql etc. setup and I need to put my
machine on external IP. But I need help with the firewall config. I tried
going through the iptables entires, and the linux-mini-firewall-howto, but
couldn't get it in my bones and feel that I may as well goof something up.
So I'm looking for help.
 
The system has 2 NICs, one on local wire, and other would get the external
IP. I need to make sure that the external client's-IP/IP-range should be the
only one accessing a particular service of the server e.g. http/80, or
ssh/22. And for the rest of the world... everything blocked. Along with this
the local network's systems should be able to access everything as usual.
What should I configure and how, please help.
 
p.s. - My co. might need one more guy in the coming month, and if someone of
you is from Chandigarh, and interested for a Job I can forward your resume
as a sys. admn. Thx.

thanks,
Aseem.