Go to Web of Science (also linked on home page Key Resources list)
Click on Journal Citation Reports at the top of the screen
You can choose the type of report that you wish to generate.
Journal Citation Reports include Impact Factor, 5-Year Impact Factor, Eigenfactor™ Score, and Article Influence™ Score.
Eigenfactor.org is a free resource which ranks scholarly journals in the natural and social sciences and also lists newsprint, theses, popular magazines. See http://www.eigenfactor.org for more information and to search for journal scores and cost-effectiveness information.