The American Library Association is a sponsor of the Amelia Bloomer project, which looks each year for children's literature (both fiction and nonfiction) with strong female characters.
Your local library is a great resource. Ask the librarians at your local library. They should be able to make some suggestions and recommendations.
It is important to remember that fairy tales operate on many levels - they are archetypal and symbolic, and while we as adults often read them very literally, children are sometimes more open to underlying messages. Put simply (and probably over-simply), we are not meant to associate only with our own gender in the story, but to relate to all characters in the story, irrespective of gender. So when I read Cinderella as a girl, I see myself not only as Cinderella, but as the prince, and the stepmother and the godmother and the stepsisters. I connect with a part of myself that wants to be beautiful, a part that wants to rescue, a part that is jealous and petty, a part that is kind and generous...
Some specific titles that portray strong female role models:
- Author Jane Yolen might be of particular interest to you as she has written many fairy tales that emphasize the strong female character. She is also the author of Touch Magic: Fantasy, Faerie and Folklore in the Literature of Childhood which explores the importance of fairy tales and mythology.
- Robert Munsch's The Paper Bag Princess Take a look at his works and see if something resonates.
- Sun's East, Moon's West by Merrie Haskell inverts the traditional questing prince format for a questing princess. And while I have yet to read The Princess Curse, at least from the description, it looks to be exactly what you're looking for.
- [Mafalda][(http://www.quino.com.ar/) hates soup and loves Beatles. Supercharged with adult attitudes, Mafalda is just too good to ignore.
- Andrew Clements: The School Story and The Landry News. The first has a 12-year-old girl who has a determined girl friend (i.e., also passes Bechdel test) who helps her get her novel published. The second is about the new girl in class who publishes her own newspaper and shakes up the teacher who was in a rut in the process.
- Ellen Klages: The Green Glass Sea. An 11-year-old girl joins her scientist dad in Los Alamos in 1943.
- The A Mighty Girl website contains articles and product suggestions for empowering girls of all ages on a wide range of topis. Their Facebook page is also updated daily.