Resources for Biographies:

In the Library:

• The Encyclopedia of World Biography (beige books under the windows) contain short biographies of a variety of famous persons from all walks of life and periods of history. 
• 920 & 921 are the section for collective and individual biographies.
• REF 920 contains encyclopedias of biography  of all types.
• Use the library catalog to help you locate specific individuals or ask the librarian for help.

Online:

Santa Clara County Library Biography Databases (Requires Public Library Card):  http://www.santaclaracountylib.org/database/subjects/biography_rpa.html

Women:

National Women's History Museum: Covers biographical information of women organized by fields of interest  http://www.nwhm.org/Education/biographies.html

Scientists: 

PBS People & Discoveries:  http://www.pbs.org/wgbh/aso/databank/bioindex.html

Galileo Project:  631 Biographies of Scientists from the 16th and 17th centuries  http://galileo.rice.edu/Catalog/New/search1.html

Profiles of Science:  Focuses on scientists involved in biomedical and health sciences.  http://profiles.nlm.nih.gov/

Nobel Prize Laureates:  If your scientist won the nobel prize a brief biography will be here on the official site for the Nobel Prizes.  http://nobelprize.org/nobel_prizes/lists/2007.html