[CentOS] how do I create a custom CD from an existing CD?

Hi all

This may sound funny, but I can't get onto any websites right now, so I 
can't even google. I want to customize the contents of my CentOS 5.1 x64 
CD, and re-create the ISO to write to CD again and install on a server. 
I know it's got something todo with mkisofs, but I'm not 100% sure what 
the commands should look like

Can someone please give me a sample of the whole command needed for such 
an operation?

-- 

Kind Regards
Rudi Ahlers
CEO, SoftDux

Web:   http://www.SoftDux.com
Check out my technical blog, http://blog.softdux.com for Linux or other technical stuff, or visit http://www.WebHostingTalk.co.za for Web Hosting stugg