Collin County Republican Men's Club
- Supporting the Republican Party and Republican candidates in Collin County, Texas
- http://www.ccrmc.org/

Collin County Historic Preservation Group
- Promotes the preservation the historical heritage of Collin County and North Texas. Includes events, newsletters, meetings, and publication.
- http://collincohistoricpreservation.org/

Democratic Party of Collin County
- Official site. Includes information on events and fundraisers.
- http://www.collindems.org/

The Political Graveyard: Collin County, Tex.
- Information about politicians who were born or died in Collin County.
- http://politicalgraveyard.com/geo/TX/CO.html

North Collin Habitat for Humanity
- Christian nonprofit building affordable homes. How it works, information on volunteering or donating, and descriptions of future projects.
- http://www.ncc-habitat.org/

Collin County, Texas Genealogy
- Volunteers do lookups as a courtesy for individuals seeking information on their ancestors. Provides message boards and links to other resources.
- http://www.rootsweb.com/~txcolli2/

The Collin County Genealogical Society
- Official site of the society, which is based in Plano, Texas.
- http://www.rootsweb.com/~txcolcgs/index.htm