To do a preemption check to ensure that no one else has written on the topic that you have in mind, you will want to do some thorough research. A logical way to do this is to start with the easiest full-text databases to search across many law journal articles at once. Each of these databases has a different collection of law journals, and sometimes there will be overlap. After running searches in full-text databases, you will want to search some free databases where people publish articles before they are officially published. Then you will want to search the Indexes, these databases cover a wider variety of journals, some of which will be outside of the scope of the full-text databases. Indexes largely provide you with information about the article, and usually have an abstract that will let you know whether or not the article is on your topic. If you want to see the full text of these articles, you may need to place an interlibrary loan if they are not available in the UC Law SF full-text databases.
Some sample searches are provided below. You can use the key words from these searches in other databases.
These resources may be useful to ensure that your topic has not been written in a non-law journal, but these databases may also be useful later when you are doing research for your paper, because you may want to use knowledge (including statistics) from other disciplines to support your arguments.
Search for the by journal title in:
If you have a citation and you cannot decipher what the abbreviation means, you can use:
The Bluebook by 
Prince's Bieber Dictionary of Legal Abbreviations by 
If an article you have found is not in a law journal, and not in one of the online resources at UC Law SF, you may want to search the online databases collection at the:.
See the Citing References tab for each of these articles to find other related sources. The final article is a bibliography that will direct you to more leading articles in the field.
"Thirty years ago the Indian law community was small enough that it was possible for even a scholar new to the field to keep up with most of the Indian law scholarship published annually. However, as our field has proliferated, it has also fragmented, and today more than two hundred pieces of new legal scholarship are published annually in law reviews alone.* These law reviews are not just ivory tower musings; there are now some scholarly contributions which are as fundamental for the study of Indian law as many cases or statutes. These articles help to contextualize the changing doctrines announced by the Court, reconcile contradictory authority, challenge assumptions of race/place/power, and push for courts, tribal leaders, legislators, lawyers, educators, and students to adopt new ways of thinking about our fundamental doctrine. However, with so many new contributions we realized that new scholars may miss some of the most impactful articles, and even the progenitors of the field will have forgotten about some of the best ideas put forward by colleagues over the years. While several federal Indian law textbooks exist to preserve judicial doctrine, there is no definitive collection of related legal scholarship." - Grant Christensen, Melissa L. Tatum.