This new site Invisiclues appears to be a labour of love of one person and promises to be “dedicated to (1) archiving historical Infocom-related artifacts -- InvisiClues, of course, but also magazine articles, marketing material, packaging, artwork, literature, and the games themselves -- and (2) making the archives available in an enjoyable format.”

Quite a lot of material there. Thanks to Andrew Plotkin on Mastodon for linking to it on his post here