It is always important to validate your findings. For case law updates your most reliable updates will be via KeyCite and Shepard's.
You can also update changes for free via the official US Code's Cite Checker. (seem below).
Amendments and changes to a statute from the legislator since the statute was last codified can also be updated via the OFFICE OF THE LAW REVISION COUNCIL web site for free! The tool you need to use is the The United States Classification Tables. tool. This source will indicate which sections of the Code have been affected by recently enacted laws since the code last was published! These tables are arranged by Congress and then Session.
Is there a proposed legislation that might have an effect your statute? To locate current bills go to:
Congress.Gov . This web site is maintained by the Library of Congress and very useful for tracking current legislation as it wends its way through Congress. Access is free and all you need to do is search this database and filter your findings.