A great place to start research on a new topic is with an encyclopedia which will give you a broad overview of your topic
Other GOOD QUALITY sources for biographies:
Spartacus Educational - Information about all people involved in Women's Suffrage
National Women's History Museum - biographies of women that have impacted the world
My Hero - stories about people that have had a positive impact on the world
Social Welfare History Project - information on people invovled in history of American social welfare
All Music - biographies of musicians
All About Jazz - biographies of musicians