I find that there's more variety in yuri manga than there is in yuri anime...I don't mind the occasional schoolgirl story but I also like more variety. (Which is why, out of the two big yuri anime of last summer, I preferred Simoun over Strawberry Panic. At least Simoun wasn't a doinky MariMite ripoff. Oh, and Kannazuki no Miko was doinky.)

Lililicious (http://www.lililicious.net) has some good stuff - I especially recommend Yamaji Ebine's works.