Global Invasive Species Database (GISD) gives free, authoritative information about introduced species that threaten native biodiversity.
Early Detection and Distribution Mapping System (EDDMapS) is a web-based mapping system for tracking invasive species distribution.
The Environmental Law Institute provides law and policy solutions that promote environmental progress, including several invasive species management reports.
Invasive.org provides a comprehensive list of invasive species in the U.S., including plant botanical & ecological information. Invasive.org is also home to the Bugwood Image Database.
National Association of Exotic Pest Plant Councils
North American Invasive Species Management Association
National Environmental Coalition on Invasive Species
National Invasive Species Council
Plants.usda.gov provides range maps and some basic information about both invasive and native plants.
USDA National Invasive Species Information Center
Invasive Plant Atlas of New England
Mid-Atlantic Exotic Pest Plant Council
Southeast Exotic Pest Plant Council
Illinois
Illinois Invasive Species Council
Indiana
Indiana Invasive Plant Species Assessment Work Group
Indiana Invasive Species Council (IISC)
Indiana's "Most Unwanted" Invasive Plant Pest List, compiled by the Indiana Cooperative Agricultural Pest Survey (CAPS)
Michigan
Michigan Invasive Species Coalition
Minnesota
Minnesota Invasive Species Advisory Council
Missouri
Missouri Invasive Plant Task Force (MoIP)
Ohio
Ontario
Ontario Invasive Plant Council
Wisconsin
Invasive Plants Association of Wisconsin
Wisconsin First Detector Network
Wisconsin Invasive Species Council
See MIPN's CWMA page for a list of Midwestern CWMAs