Once Upon a Fic Exchange

For people looking for sources for Greek/Roman mythology, can I humbly suggest Theoi.Com? They tend to exhaustively document resources, so if you're looking to compare differences in various retellings of myths (did Persephone eat 4 seeds or 6? Did Hades get hit by Cupid's arrow or not? etc), they have an almost exhaustive amount of sources you can look up (and an almost exhaustive amount of full-text sources are on the site as well)