With Sailormoon being a story that has encompassed a variety of media, from manga, to animation, to music, to stage, it is only reasonable to assume that many sites can build their whole purpose around serving up a sliver of entertainment. Many of the listed image galleries were used in the making of this site, and hence deserve credit where credit is due.

Lycentia's SM Web Graphics Shop: Dozens of pre-made layouts, buttons, game sprites, and other web graphics. I haven't directly used anything of hers, but her tutorials are excellent and the layouts are great for ideas of my own.

An Eternal Moonlight: I found this site while looking for images. It's got a wonderful image gallery, and it's also got some nice other stuff that isn't covered on other sites.

Manga Style: A wonderful site dedicated to scans of the Sailormoon Artbooks. Also features translations of the liner notes.

Serenitatis: Gigantic gallery of pictures of Usagi and Mamoru in all their various incarnations. I don't know how Hoshichan pulls it off...

Sailor Galleries: Small image galleries of each senshi, as well as wallpapers and artbook scans, but the huge fanart gallery is easily the highlight.

Solar Miracle Make-Up!: A vast site dedicated to SeraMyu, the Japanese Sailormoon Musicals, including reviews, MP3s, and images.

Sailormusic.net: Very nice Sailormoon OGG Vorbis music archive, with a rotating schedule and some rare, permanently hosted tracks.