[CentOS] Download the repo DAG of CentOS 5.5

Sun Apr 3 18:12:55 UTC 2011
Fidel Dominguez-Valero <fdvalero at gmail.com>

hello
somebody might help to create a script to download the repo DAG of
CentOS 5.5 to my PC. I already did with OS, Update, and Extras packages.
I want to do with DAG repository.

I tried but I don't know much about scripts.
Thanks
Fidel