I did a Google search for "wausau bulletin boards" hoping to find a listing of different places you could post flyers but nothing came up. So a friend and I decided to begin trekking around looking for potential advertising spots that are open to posting. Here is a map of the ones we've found so far:
Updated as of 25 February 2013
View Bulletin Boards in a larger map
Remember to ask permission before posting and bring your own tacks / push pins.