To retrieve a legislative history, you'll need to know the Public Law number for the statute's original enactment and/or any amendments you would like to research.
To get started, access the statute in any version of the United States Code. The official, government published U.S.C. is available in print and on HeinOnline. Lexis provides the unofficial U.S.C.S. and Westlaw provides the unofficial U.S.C.A. All will provide the same basic history information.
Usually, it's easiest to type the citation into the main Lexis or Westlaw search box, in the format 18 USC 711A. You can also browse to the statute in any of these versions:
Once you've accessed your statute, scroll down to locate a section listing Public Law (Pub. L. or P.L.) and Statutes at Large (Stat.) citations.