Once you clearly understand your objective, you will begin to analyze it as a research question to determine the sources and approaches most likely to best answer your question.
Suggested Research Plan
Analyze the problem: Is it governed by federal, state, or local law? We know we are working with the Federal Claims Act so, generally speaking, we are dealing with federal law.
Is the area of law or issue unfamiliar? If so, begin your research with secondary sources. They will cite to primary materials and will also provide the background and contextual information you need to understand the primary sources.
Possible sources: ALR annotations, Causes of Action, legal encyclopedias, treatises, practice materials, law review articles.
Are statutes or court rules relevant? We clearly have a relevant statute - the False Claims Act. Consult a federal annotated code such as USCA on Westlaw or USCS on Lexis. The annotated codes will provide the text of the statute or rule but will also lead you to cases, regulations, and other relevant materials that discuss your issue.
Identify a relevant case:
(1) Once you've located a highly relevant case using a treatise, annotated code, or similar source, use that case to find additional cases on point. Tools for finding more cases: the topics and key numbers on Westlaw, "search by topic" or "more like this headnote" on Lexis, citators (Shepard's or KeyCite).
(2) After having familiarized yourself with the necessary background information you'll have the ability to generate relevant keywords to use for keyword searching in the online (federal) case law databases.
Review your findings: What unanswered questions remain? Did your research raise new issues you need to investigate? Look back through the process as necessary until you've closed any remaining gaps in your research.
Update your work: Verify that the key authorities you are relying on are still good law using a citator service such as Keycite or Shepards. If you are using other sources, such as statistics, confirm that you have the most current information available.
When are you done? When every new source or strategy directs you to primary authority you've already found, you can be confident you've thoroughly researched the problem.