Indoor Spraying can occur in female cats, but that is far less common than in male cats. Also, desexing is not a guaranteed way to prevent spraying. Sometimes, cats that have never sprayed before when intact start spraying after being desexed.

Websites
1) Hormonally Intact and Responsible - Cats: http://intactcatsresponsiblecare.weebly.com
2) Intact Cat Resource: http://intactcatresource.proboards.com