Top Eight non-Lovecraft Cthulhu Mythos stories. It was supposed to be ten but some of my books are in the attic and so I only managed eight favourites. The first two are available on line. I suppose a few are not strictly Cthulhu Mythos, but they do have the Mythos Ethos.
A Colder War - Charles Stross
The Cold War meets the Mythos head-on
A Study in Emerald - Neil Gaiman
Holmes' London as it never was
The Courtyard - Alan Moore
Grimy and grim, with drugs.
The Willows - Algernon Blackwood
Otherworldly interactions on an island in the Danube.
Suicide Watch - Arinn Dembo (Dark Theatres)
Nirvana as Mythos.
The Yellow Sign - Robert Chambers
Lugubrious and creepy.
Cold Print - Ramsey Campbell
A warning on second hand bookshops.
The Tsalal - Thomas Ligotti
An occult cult does what it must