Email is the fastest way to reach us. Some things have a quicker route through the site, and those are below.
Usually answered within a day or two. If it's been longer, send it again rather than assuming you were ignored.
Every wallpaper has a Report button under its tags. That puts it straight into a review queue rather than an inbox, so it gets looked at sooner.
Read the copyright page first. It lists what a takedown notice needs. A report will get it seen, but a proper notice is what starts the formal process.
Do it yourself from settings. No waiting on a reply. Profile, uploads, follows and download history all go. Files other people already downloaded can't be recalled. Nobody can do that.
Bugs, ideas, wallpapers that render oddly on your particular screen, anything that reads wrong. All useful, all welcome.
If you make wallpapers and want to publish here, just start uploading. No application, no approval queue.