I'm not a very big fan of Glinda/Elphaba, though in my case it's because I love Fiyero/Elphaba to itty-bitty pieces. The fandom tends to be...homogenous, to say the least. I might try starting a non-Gelphie ficathon, but I'm wary of getting my head bitten off.

Have you tried West Side Story fandom, if it has one? There might be some Maria/Anita kicking around. I know for a fact there's a Kathy/Lina (Singin' in the Rain) fic here (http://romantic.frenchboys.net/petra/srsotto.html).