In addition to “other duties as assigned”; recruiting, training, and managing volunteers are primary functions of many Volunteer Managers at rape crisis centers.  The Corporation for National & Community Service collects data on a variety of subject areas regarding volunteering in the United States of America.  Many of the reports compartmentalize the data by state, county, and city.  You can find reports that provide information on volunteering trends, where people volunteer, why people volunteer etc.  This information can be useful in the recruitment of volunteers, marketing your program and sustaining volunteers.
Additional Information
The New Volunteer Workforce
Health Benefits of Volunteering
Volunteering in America 2010 Brief
Volunteering In America 2010 Fact Sheet