Use these links to get the ISOs you will need to burn:
- CentOS 7 Live CD: http://mirror.csclub.uwaterloo.ca/centos/7/isos/x86_64/CentOS-7-x86_64-LiveGNOME-1503.iso
- CentOS 7 Full Install DVD1: http://mirror.csclub.uwaterloo.ca/centos/7/isos/x86_64/CentOS-7-x86_64-DVD-1503-01.iso
There is also a Live CD and a second install DVD, but we won't be using them.