Once you have an idea for your research, you need to begin looking through secondary sources--meaning journal articles, books, and treatises--to get a solid understanding of your chosen area of health care law. A good foundation article or treatise can save you a great deal of time, both in getting familiar with the topic and in finding references to the significant primary sources you will need to cite in your work.
There are an extensive number of medical-legal journals available through both the UR Law Library and online. This is list in not at all exhaustive but may be a good place to start looking.
Remember that Westlaw, Lexis, and Bloomberg all have search features that will let you look for books, treatises, and journal articles. The available journals and books in each commercial database do not overlap completely--Lexis, for example, will have Matthew Bender treatises while Westlaw will have Thomson Reuters and West publications--so a thorough researcher will check all three.
In addition to journals focused on healthcare law, you may occasionally find it helpful to consult with science and medical journals when you are beginning research on a topic you are not very familiar with. While it's important to exercise good judgment when reading materials outside your field of expertise, these journals can be helpful if you are beginning research involving a health or healthcare topic if you need to, for example, get a basic understanding of terms involved in order to devise a strong search strategy.
Both the legal and health professions are known for having a lot of complicated vocabulary. If you come across a medical term you do not understand, try a health care-specific reference resource to get a definition. Often, you'll get a better explanation that a basic dictionary and you'll be given related terms so that you will recognize them as you research.