A fellow I bought my '70 Mach 1 from had a great idea: hit auto body shops. The older the better and rural ones were the best. Many a shop has a big fenced in area out back where wrecks, cars under restoration, abandoned cars and cars they just kinda' ran across are stored. 
You have to 'work' the manager or staff a bit to see what's out back though. Often, the cars are NOT picked over since they are not junkyards. My seller would bring a box or two of donuts as he walked in the door. Talk about flies to honey! 
Another trick was hitting closed-down gas stations, body shops, dealerships, et al. This was more work since no one is around but if one saw their dream car out back, a call to the bank's phone number (it's always on a slapped-on paper poster on a front door) will usually lead to the fellow in charge of repo's and the property.