If you haven't been able to find a compiled legislative history, then your next option is to locate a list of citations. Working from this list, you can then gather the documents yourself and compile your own legislative history.
The resources listed here offer varying levels of breadth and depth. For instance, a law may take multiple sessions of Congress to pass, but a list of citations may only be from the session that passed it. Also, even within a list from one Congress, it may omit citations that are more tangential or certain types that are less important, like hearings.
Please note, access to certain databases linked in this guide may be restricted to UT Law or the UT community; please see the library's Databases page that lays out access privileges.
The most comprehensive lists come from the Congressional Information Service (CIS), which is owned by Lexis, made available two different ways:
Image from ProQuest Congressional.
U.S. Code Congressional and Administrative News (USCCAN) is a unique resource published by West, available on Westlaw. It offers two sets of volumes per Congress: one set is a reprint of the Statutes at Large and the other set is labeled "Legislative History," containing lists of citations, selected, abridged reports, and presidential signing statements.
Thus USCCAN has characteristics of both a compilation and a list of citations. However, because it reprints only highlights from a law's legislative history, it is not a comprehensive source as either a compilation or a list. Still, it can be quite convenient to use--you will find references to the relevant portion of USCCAN listed section by section in the USCA. And because it focuses on the highlights, it can be a good first source to check.
Westlaw's "Graphical Statutes" and "Legislative History" Features
In addition to compiled legislative histories, Westlaw offers two features that are integrated into the search results from the U.S.C.A. or Public Laws databases. (The Graphical Statutes feature is noteworthy in that it offers a visual timeline of the changes to a section of the Code.) Keep in mind, however, that it is still worthwhile to seek out a full compiled history or a list of citations for comparison. Also, the links to testimony provided are unofficial transcripts of hearings, not the final, official versions that are published later.