Other Than The Sims Resourse...?

I use sims4updates.net It has links to a fairly vast number of great sites where some really good cc of all types are housed.

You'll find lots of wall coverings (and other sim-stuff) on Tumblr as well. I just did a search here. Mostly interior, though, but some brick as well. Didn't go through the entire page, so could be other types of walls. I'm working on walls too, but haven't added any yet. Need to make sure I'm using free stuff to make them, before uploading.

Ia Tumblr free and safe to use?

@Patrice It depends on where they actually upload the CC. If they use SimFileShare, it’s fine. I’ve never had a problem with Google Drive or Mega.nz either. Mediafire sometimes sends you to a random website when you click “download”, and a pop-up blocker doesn’t help. You should still remember to use one, though, in case someone uses Adfly or other link shorteners.

Stay away from Simsdom- I’ve heard that it’s full of viruses, and most of the CC there was probably uploaded without the original creators’ permission.

I really like Modthesims.info. It's big for mods, but it has some CC there too that's quite nice imo

I always use tumblr for cc. I'd recommend the Maxis Match CC World blog, they have filters so you can just look for wallpapers specifically, here:

https://maxismatchccworld.tumblr.com/buildmode