Learned this from friend PI. You can go to the official website for many cities and towns, and most offer online payments for excise tax. On many, all you need is the license plate number. Plug it in, the site thinks it's yours (I mean really, who else wants to pay your taxes!), and owner info, address, vehicle's VIN/make/model/year, and how much tax is owed (or late). Just another free resource, which can be helpful if you're just trying to confirm info that you already suspect.