The Wisconsin Department of Natural Resources in conjunction with the University of Wisconsin Sea Grant Institute and the UW Extension have prepared an informational brochure to help boaters "prevent aquatic hitchhikers from catching a ride on [their] boat or equipment." The publication helps readers identify zebra muscles and outlines ways to remove both adults and larve from boats and prevent their spread to other waterways. You can obtain a PDF version of the publication here and a "Clean Boats, Clean Waters" poster here.