Hehe I don't think you looked too hard. This link was from their products page:
http://www.redhat.com/rhel/details/eval/
I'd recommend talking to a Sales Engineer at Red Hat and asking their advice if you're serious about a move. They can really help with the nuts and bolts. If you want a referral, let me know and I'll email you off-list.
Jeffrey.
RedHat does not offer trial copies. The closet you can get to that is
Centos (which is arguably closer than a trial copy would be)