Rod Serling

(not sure if this is right but;) How do we go about getting a Legacy Library for Rod Serling?

First of all, you need to find a source for the books he owned (this could be a published bibliography, an auction catalog, etc.). Depending on the source, you may need to get permission to use it. Once you've done that, proceed as described here: https://wiki.librarything.com/index.php/Cataloging_Guide