Want to contact your local elected officials? You've gotta find 'em first.
In my neck of Michigan, for example, Town Hall located not only the governor and lieutenant governor, but also my state representative. Also listed: House and Senate reps, the veep and POTUS. According to a Facebook spokesperson, Town Hall currently shows local elected officials for about 150 cities, with more to come.
To find Town Hall in your desktop browser, look to the Explore section on the left side of the Facebook page. If you have a lot of items there, you might need to click See More to find the Town Hall entry. Unfortunately, at present there's no way to edit that list, should you want to move Town Hall closer to the top.
In the Facebook app, tap the Menu icon (the three stacked horizontal bars) and look for Town Hall. If you don't see it, once again look for the See More option.
For any given representative, you can tap Follow and/or Contact. The latter option varies depending on whether you're in a desktop browser or the mobile app. In a browser, clicking my senator's Contact button produces a window with his mailing address and phone number. But tapping Contact in the app produces Call and Visit Page buttons.
On either platform, you get two additional options for contacting local representatives: Email and Message. Yep, Facebook now offers arguably the fastest, easiest way to electronically contact your state reps.