Link to 8/26/2011 Wispolitics news release.
Note that this is the current map of the 33rd Senate District, i.e, the one that went into effect in 2002. You can view the new boundaries at the Wisconsin State Legislature Legislative Redistricting webpage. Generally speaking, there's a westward shift in Waukesha County, a redrawing that will solidify the Republican majority in the 5th Senate District. (Walker signed the redistricting bills --Acts 43 and 44 -- but a second federal lawsuit alleging the legislature's maps are unconstitutional is still pending. The first lawsuit was dismissed in late July by a penal of federal judges in Milwaukee.)
Libraried communities include, from top to bottom, Hartford, Sussex (joint library with Town of Lisbon), Pewaukee, Brookfield, and Waukesha. And, yeah, I should have double-checked the Wisconsin Blue Book before saving the screenshot, as a portion of Menomonee Falls is also within the 33rd Senate District.