Truck Stop - 3X3 massive gas station with lots and lots of well-spaced pumps. Appears outside of towns and most frequently by major highways. Spawns even more than usual of the normal gas station stuff plus a small amount of random general civilian loot (you can buy the weirdest stuff in big truck stops) and might even rarely spawn with a semi tractor parked out front.
Trailer Park - 3X3 site with several small house trailers parked around a cul-de-sac drive. Good chance of finding a meth lab or something similarly shady.
Apartment Building - 3X3 site consisting of hallways and sets of residential rooms (maybe just bedroom and bathroom) and a high concentration of the undead.
School/College - Another 3X3 site; grab books from the library, sporting goods from the gymnasium, tools from maintenance, and food from the kitchen in the cafeteria. It’s one stop shopping.
Auto Parts Store - Contains loot similar to a garage but no cars. Just a storefront type structure that spawns full of shelves of loose vehicle parts and related tools.
Head Shop/Dispensary - For those of you who might not be aware, a head shop is the place where folks go to procure bongs and fancy rolling papers and whatnot. Basically just a store site that contains lighters and crack pipes, and cigars/cigarettes in the front room as well as a small stock of illegal-type drugs in a securely locked back room. Pretty much serves the same purpose as a pharmacy for post-apocalyptic druggies, but specializing in non-medical substances.
Lumber Yard - 3X3 site surrounded by a fence with a store in one corner that carries woodworking-specific products and piles of logs and 2X4s and such outside the store area, inside the fence.