The US Senate has set up a Small Brewers Caucus to discuss issues related to small breweries.
The Caucus is a bi-partisan effort and was led by Max Baucus (D-Montana) and Mike Crapo (R-Idaho). Which is interesting because Idaho isn't exactly Beervana (it is home to craft beer raw material producers); though Montana's craft beer scene is booming.
It is not clear yet who the members of the Senate Small Brewers Caucus are, but I hope that Senators Herb Kohl and Ron Johnson will consider joining the effort on behalf of the small brewers here in Wisconsin.
The House has a Small Brewers Caucus as well. The only Wisconsin Representative that is involved with this caucus is, unsurprisingly, Tammy Baldwin (D-Madison). If you are a brewery maybe it might behoove you to encourage your Representative to get involved with this Caucus.
I'm not aware of any such caucuses in the Wisconsin State Legislature.
Finally, I've been asked by a number of brewers whether I think joining the Wisconsin Brewer's [sic] Guild is worth their time and effort. My advice has mostly been non-committal; but I would suggest those thinking about joining consider what benefit the Brewers Guild provides that they wouldn't otherwise enjoy.
In other words, there is a big free-rider problem for the Brewers Guild - it undertakes action on behalf of its members that will benefit non-members. For example, whether Brewery X joins the Guild or not, the Guild will still undertake Lobbying efforts that will benefit Brewery X. Thus, should Brewery X spend money to receive a benefit it would receive without spending the money? Maybe. Maybe not.
So, what specific benefit does membership in the Guild provide for Brewery X? This post is not going to outline those, though the Guild's website outlines some of the benefits, namely: "lobbying", "meetings", "link to your website." If the dues and administrative hassle are worth that benefit to you, then, yes, you should join. Or at least talk to a member and other brewers about whether the benefit is worth it to them.*
* For the record, I've spoken with a number of brewers who have answered both affirmatively and negatively. So, ask around.