Amphibians and Reptiles in Collin County: Texas Cooperative Wildlife Collection list of species found in the county.
Butterflies of Collin County, Texas: Information about and pictures of all the known species of butterflies in the county.
Collin County Law Enforcement Academy: General information plus class schedules and on-line registration.
Collin County Psychological Association: Provides information to both Psychologists and people needing their services.
Collin County Texas Index of Landmarks & Vanished Communities: Location information for landmarks and vanished communities in the county.
Fire Fighter Clark's: Site with links to local Fire Departments in Collin County. Home of 2 ISO Class One departments.
Handbook of Texas Online: Collin County: Current and historical information about the county.
League of Women Voters of Collin County: Non-partisan organization encouraging informed and active participation of citizens in government.
Native Plant Society of Texas: Collin County Chapter: Includes contact information and a schedule of meetings.
Prairie and Timbers Audubon Society: Chapter of the National Audubon Society, located in McKinney, Texas.
Rape Crisis Center of Collin County: Information on the effects of all types of sexual assault, and the services that the center provides. All information is available in English and Spanish.
YB Lost - Collin County, Texas: Provides names and addresses of county public officials and departments.