Here are some good resources to get you started with legal research:
Library of Congress' Guide to Law Online
"The Guide to Law Online, prepared by the Law Library of Congress Public Services Division, is an annotated guide to sources of information on government and law available online. It includes selected links to useful and reliable sites for legal information."--Library Website
The U.S. has a federal system of government, meaning that there are separate federal and state governments that share law-making authority for the same geographic territory. Both the state and federal systems have three branches of government: legislative, judicial, and executive. Each branch is a unique source of law.
In evaluating legal authority, a researcher must consider if that authority is mandatory or persuasive. Researchers must also be able to identify primary and secondary sources of law. Primary sources of law issue from a law-making body and are, in essence, "the law itself." Primary authority can be either mandatory or persuasive. Secondary sources comment on or explain the law. Secondary sources are always persuasive, rather than mandatory, authority.
For More Information:
Here are some databases that are available to you from the Duquesne Center for Legal Information (DCLI), aka the law library:
Before you begin any research project, you should try to make a habit of writing out the issue or issues that you intend to research. Being able to articulate your research goals is important.
There are various ways of keeping track of your research and taking notes. Do what works best for you. That might be a written checklist or research log, or some other method. It may well be a combination of methods.