The DoD CIO gave an overview of the Risk Management Framework (RMF) transition. The Risk Management Framework Knowledge Service (RMFKS) is a central repository for RMF DoD for IT. This site is up for access as long as you have a Common Access Card (CAC) or ECA cert. The link is below but some of the links on the site are still under construction.
The former site was for certification & accreditation / risk management was the DIACAP Knowledge Service (https://diacap.iaportal.navy.mil/).