Are any of the titles for 5th Edition out of print? There are a handful of titles that seem hard to track down locally. I'd like to know for sure that they're no longer available before I resort to searching online and paying extra for shipping.
As far I as know, Houses of Hermes: Mystery Cults and Societates are out of print: https://forum.atlas-games.com/t/hoh-mc-reprint/3602/1
A good way to check is to look at the Warehouse 23 catalogue. If they don't have the print version listed, it's probably out of print, since that's where our on-site "buy it" links point.
http://www.warehouse23.com/info/arsmagica.html
Obviously, it's not perfectly reliable, but it's probably the best way to quickly check. (I don't know what's in and out of print; stock management is someone else's job.)