Mercer County Democratic Party
- Official site with election results, campaign schedules, event calendars, and volunteer opportunities.
- http://www.mercerdems.net/

Mercer County, New Jersey, Genealogy
- Resource site providing surname lists, a database of migrations, maps, a message board, and links.
- http://members.cox.net/mercergen/mercer.html

The Political Graveyard: Mercer County, N.J.
- Includes demographic and geographical information, plus lists of cemeteries, and short biographies of political figures who were born or died in the county.
- http://www.politicalgraveyard.com/geo/NJ/ME.html

Pet Rescue of Mercer
- An all-volunteer, not-for-profit animal rescue group. Includes a vision statement, donation details, and upcoming events.
- http://www.petrescueofmercer.org/

Online Volunteer Clearinghouse for Mercer County NJ
- Contains information on volunteering opportunities throughout the county.
- http://www.handsonhelpers.org/

Mercer County, NJ History
- Discusses the importance of the county, with biographies, census data, event schedules, and links to area resources.
- http://www.rootsweb.com/~njmercer/

Mercer County Genealogy Forum
- Message board for individuals seeking and sharing information.
- http://genforum.genealogy.com/nj/mercer/

Howell Living History Farm
- County owned historical site with a FAQ, photos, visitor information, internship details, and barn restoration progress updates.
- http://www.howellfarm.org/

The Arc Mercer
- Advocacy and resource group for the mentally disabled. Offers a mission statement, history, board member directory, program information, calendars, and a newsletter.
- http://www.arcmercer.org/