Onalaska, Wisconsin is reportedly the site for the state's second Tesla Supercharger.
La Crosse Tribune is reporting that construction of a Tesla Supercharger with six stall began in the city of Onalaska on December 2, 2013. The site is expected to be operational really soon
UPDATE: Really soon actually means it's operational now
This particular station is located "off Midwest Drive in the parking lot of Reed Music Studios," according to La Crosse Tribune.
Wisconsin's first Tesla Supercharger is in the city of Mauston. After Onalaska comes online, Wisconsin will have two of its 5 proposed Tesla Superchargers.
Additional Superchargers are planned for the cities of Madison, Pleasant Prairie and Eau Claire.
UPDATE: This Supercharger has been confirmed to be operational, yet Tesla's site doesn't list it yet.
Source: LaCrosse Tribune (Thanks to ABC for the tip - and KmanAuto for the video below)