Municipal Data System
, an online database of annexation petitions and ordinances, including information on the annexee and annexor municipalities, the size, location, population, and date of the annexation. Also included are images of the submitted annexation documents, such as the scale map.
"Annexation of Territory to Wisconsin’s Cities and Villages", by the League of Wisconsin Municipalities. The guide describes the various methods of annexation, and provides relevant court decisions and model forms. For copies contact the League http://www.lwm-info.org/