As an aspiring archaeology student, you will reach the point of the graduate application process. At this time, you will need to figure out your focus and what you are planning to accomplish. All of the archaeology graduate schools you are applying to will need a letter of intent and Lesley Nicholls from About.com just provided us a wonderful and helpful Guide to the Application Process for Graduate School.
Many schools request a short statement or 'letter of intent' from you laying out research interests and the reasons why you are applying to graduate school and to that particular school. This is the document that will sell you and your research interests to the department, so for heaven's sake take as much care in preparing it as you would a term paper.Read this article once, twice, and ten more times until you understand the process.
Also check out
A Guide to Applying to Graduate Schools in Archaeology