Last time I bought them was the Close Combat series from Slitherine/Matrix Games, which does war games.

checks

Looks like they stopped last year:

https://www6.slitherine.com/news/important-update-last-chance-to-purchase-physical-manuals-and-editions-before-march-1st

Dear Wargamers,

We want to share an important update with you.

Starting March 1st, 2025, Slitherine will no longer sell physical game manuals or physical copies of our games through our website. This marks the end of an era, and we understand how much these editions have meant to many of you over the years.

There is a trend away from Physical purchases to digital, and a decreasing number of new PC’s even have DVD drives and very few laptops meaning the potential market has been shrinking for years. This, combined with increasing delivery costs, environmental awareness, and more red tape on international deliveries, all combine to make it unviable.

For those who appreciate the tactile experience of a physical manual or a boxed edition, this is your final chance to secure a piece of wargaming history. You have until February 28th, 2025, to purchase from the remaining stock, after which these products will no longer be available.