Oyonale – website of Gilles Tran, an accomplished POV-Ray artist. I don’t think it’s been updated in eleven years, though.
Friedrich Loehmuller‘s website, has some good tutorials. Don’t think it’s been updated in about three or four years, though.
Rune S. Johansen‘s website, has some tutorials, and a variety of content, not only POV-Ray related stuff. Looks like he last updated his blog December of 2019, so kind of quiet, but not dead yet.
Warp’s Homepage. Well, his raytracing gallery, at least.
He also has four tips to improve a simple raytrace scene. Could be useful.
P.O.V.-Place, an old POVRay website, which at a brief glance, has some inspiring images at least. No tutorials, though.
Christof Horman’s website. He is one of the developers of POVRay, and it looks like he still updates his website. Well, he updates his blog regularly; it looks like the rest hasn’t been touched in a few years. He does have a decent POVRay section, including tutorials.
The Persistence of Ignorance, the website of Jaime Vives Piqueres. It has some good resources, tools, and a gallery of pictures as well.
No Lights, the site of Tim Nikias. Not sure about updates, but it does have what looks like some good include files, such as a set of macros for liquid surface simulation. Might be useful.