Get Fedora. It is almost like the core RH distro, maybe better.
Also, you can try out Oracle Linux. It is pretty much a rip-off of RH.
You can install Centos which is very similar to RedHat in terms of feature and stability. http://www.centos.org/
James Van Damme
University of Ruhuna
Universitas Stikubank Semarang
Hemprasad Y. Badgujar
Shri Guru Gobind Singhji Institute of Engineering and Technology
Mojtaba Madadi Asl
Institute for Advanced Studies in Basic Sciences