I finally came across the bookcases, above, which a used bookstore were getting rid of. Because they were custom-built for that bookstore, they are of quality plywood construction, with moveable shelves, allowing me to efficiently house my Appendix N collection.
The above photo is my complete Appendix N collection, minus the books below, which I just picked up at another used bookstore yesterday.
John Jakes' Mention My Name In Atlantis and Farmer's The Lavalite World.
I Am Legend by Richard Matheson and The Mezentian Gate by E.R. Eddison.
Finally, Keith Laumer's A Plague Of Demons and Zazkor, Son Of Vazkor by Tanith Lee.