Research is a recursive process. You may find during your research or writing that a particular area needs more research and that is okay.
Organizing your research will make the process easier. Track your search language, the databases where you have searched, and organize your useful and non-useful results. How you organize is personal choice and should fit your personal style.
Feel comfortable asking for help. Faculty members and reference librarians are useful resources.
What types of sources will you need? Well that depends on what you are writing about. More often than not, scholarly legal articles and SAW paper sources may include scholarly articles, treatises, news, and primary sources such as cases, statutes, and regulations, to just name a few.
Before doing any additional searching, I recommend reading your preemption materials. Background searching is meant to build your understanding of the area you will be writing in as well as your particular issue. The materials that you have gathered in your preemption searching will likely include materials that may set out the background of your topic.
Once you have read your preemption materials you have a number of methods for expanding your background research.
Now that you have a strong foundation in your topical areas, you will want to locate primary sources specific to your topic. Primary materials include cases, statutes, regulations, and government documents such as legislative history materials and agency documents. Primary materials can be located in a number of ways.