"Lobbying" supposedly got its name from the habit of those seeking favors from Congress waiting for their Congressional representaitves in the lobby of the Willard Hotel in Washington DC. Here they could wine and dine the members of Congress and, perhaps, pass a bribe or two along with the after dinner brandy.... Of course, modern lobbyists are usually a bit more discrete.
The Government Accountability Board - Lobbying Page has a wealth of information on lobbying in Wisconsin: who does it, when they do it, when it is legal, when it is not and what happens when the rules are broken.
To use the GAB Lobbying database, you will need to go to the Eye on Lobbying website. Have fun!