Complete Federal Register Now Available in HeinOnline
If you haven't already discovered HeinOnline, I highly recommend that you take a look. It's one of the best kept secrets in legal research.
HeinOnline is probably best known for its outstanding collection of law journals, which provides comprehensive coverage from the inception of each publication. In some cases, coverage goes all the way back to the 1800s!
There are also three other major library collections: the aforementioned Federal Register Library, the Treaties and Agreements Library, and the U.S. Supreme Court Library.