For keeping track of changes in federal agencies and for finding data, these sites can help:
Finding Government Information during the 2025 Administration Transition (University of Minnesota -Twin Cities Libraries)
DataLumos, an archive for government data resources (University of Michigan's ICPSR)
OpenICPSR, also sponsored by the University of Michigan's ICPSR, is a self-deposit repository with links to DataLumos and including data from federally-funded research.
Archived Federal Data (University of Notre Dame Libraries)
Data Rescue Project Portal (supported by major data organizations).
The library subscription to Coherent Digital includes access to saved copies of reports, including from U.S. federal agencies.
Very basic advice from one experienced user of federal agency websites:
Also, watch out for material that has been quietly changed.
This work is licensed under a Creative Commons Attribution-NonCommercial 4.0 Generic License.