1) Use the ebook Major Acts of Congress and also the CQ Press Political Reference Suite and search by the name of the legislation in quotation marks, for example, "Family and Medical Leave Act", to get a basic history of the origins of the act of congress. The more you know about legislaton, such as important dates, the names of Congressional sponsors and the proper name for the legislation, the easier it becomes to focus in on information.
Use Proquest Congressional and search by the name of the legislation in quotation marks, for example, "Family and Medical Leave Act", to get government documents, hearings, and later related legislation. (Here is help finding Legislative Histories in Proquest Congressional.) Often, an act is part of a larger a public law, so you may end up searching for the legislative history of the public law in which the act is contained.
[Note: "Legislative history refers to the progress of a bill through the legislative process and to the documents that are created during that process. Attorneys, judges, and others often turn to these documents to learn why Congress enacted a particular law or to aid in the interpretation of a law. The components of legislative history for a bill (in order of their importance) are: committee reports, bills and their amendments, sponsor remarks, and committee." University of Washinton School of Law]
Use Thomas once you know when and who introduced legislation into either the House or the Senate in a particular Congress. One search to try is by the name of the sponsor/co-sponsor in the appropriate Congress. Thomas does a good job of organizing links to legislative documents in grids, but you sometimes have to burrow through the Web pages to find the relevant parts.
Do a subject search using the proper name of the act of Congress as subject in the Diamond Library Catalog to get government documents, hearings, legislation, and books on the act.
Searching the name of the legislation in quotaton marks in the Encylopedia of Social Work can sometimes provide context for the legislation.
CQ Weekly reports on Congress and federal issues and votes on legislation. Search the name of the act both in quotation marks, for example, "Family and Medical Leave Act" and without quotation marks. Sometimes the results are too overwhelming to be of much use. Often, legislation is part of a larger bill that becomes a Public Law, which makes it almost impossible to tell why someone votes for or against a measure.
Congress and the Nation Key Vote Tables gives the tallies of votes on legislation from 1946-2004. Find the appropriate Congress and browse the tables.
If you are trying to determine who supported and who opposed legislation, sometimes this gets reported in CQ Weekly in articles discussing the floor debates. You can also try using the Congressional Record, the daily official report of Congress, and search the name of the legislation to find remarks on a bill. Often, aagin, legislation is part of a larger bill or Public Law, which makes it almost impossible to tell why someone votes for or against a measure.
The Code of Federal Regulations (CFR) is the document that details how each relevant part of the federal government will implement legislation. Search by the name of the act. This can be very, very detailed.
3) Academic Search Complete Search on the name of the policy in quotation marks, for example, "Family and Medical Leave Act" to find articles on how well the act of Congress accomplished its goals or ran into problems. Also try Access World News for newspaper articles, again with the name of the policy in quotation marks. Look at the years on the left side of the results particularly for when the legislation was enacted.