If your into really old stuff try the wrecking yard on State Rt 56 just outside of Mt. Sterling Ohio, it is huge and there are cars in there dating back to the 1920's. On one trip I found 3-57 Chevy's, a 57 caddy convertible, 2-55 Chevy's, 4 56 Chevy's a 67 Mustang Fastback, a 66 LeMans convertible that was a factory triple white car (how rare was that back in 66) a complete older MGB, a 39 Ford Sedan, 2-58 T-birds...the list goes on.
There is a 57 Chevy 4 door hardtop sitting out front in restorable shape, but most of the cars inside have rusted to the point of collapse after sitting in the Ohio weather for 40 years, also have been stripped of interesting parts.
J.C. Radiator on Williams avenue here had a few really rare and interesting cars, including TWO 56 Pontiac Safari's (the rare car with the Nomad roof, 2 door wagon) a red on Red 66 GTO, an aqua 65 GTO, several Galaxy's and T-birds from the 60's, a few early 50's ford trucks, and more 2nd-3rd gen Camaros and firebirds than you could shake a stick at.
One of my favorite cars was the blue 71 Mach 1 fastback.
Also Caddys, Cutlasses, and several interesting Buicks, etc. from the 50's. None worth restoring and such but interesting to look at.
...and then one day the J.C. Radiator yard changed hands or something and they crushed EVERYTHING over about 2-3 days.
There were some interesting yards in Northwest Ohio in Amish country a few years back, but I doubt any of that stuff is still there.
The rarest two cars I ever saw were a 63 Studebaker Avanti (not continuation) and an early 911 sitting side by side in a yard on Groveport Road here in Columbus. They would not sell either car or parts off of either car, and a few days later when I went back to take photographs both of them had been crushed.
I, BTW, am not obsessed with cars or anything...
Chris