Every county, city, or municipality keeps a list of their condemned properties. If you call the permits, code, planning, zoning, whatever department, they can point you in the right direction. Code inspectors and P and Z officials are great resources for finding deals so hook up with them.
Properties don’t get condemned because one of the stairs is a half an inch too low. They get condemned for serious safety and health violations. This is why a lot of investors don’t go this route, too much work. The expense of the work can often make condemned properties unprofitable. You’ll have to sort through them all to find out which are no-go’s.