If you have a linux server and wish to install CentOS on your linux server, here is the URL where you can download from this webpage:

http://mirror.lug.udel.edu/pub/centos/5.4/isos/i386/

UPDATE: try this new:

http://mirror.lug.udel.edu/pub/centos/

Public Mirror List:
http://www.centos.org/modules/tinycontent/index.php?id=30

for more visit CENTOS.ORG
http://www.centos.org


now if that doesn't work, its better that you visit the official site for other mirrors. but at first, i thought there was no DVD version, but it looks like there is

cheers!