Don't put old vinyl into landfill! Please! If you put an ad up on CL someone will come and take them away. Sure some stuff is worthless, but let some record hound figure that out.
As far as I am aware, almost any Savers or Goodwill will take lps/45s/78s if you box them up and bring them in. Each thrift is different, and each town has different rules. For instance in the town next to mine if you walked in with a set of stained sheets and a tweed Fender amp, they would take the sheets and tell you to throw the amp in a dumpster. The sheets would eventually be hauled away to be shredded. So the thing that thousands of people would give a nut for gets destroyed, and the thing that nobody ever needs sits around.