need help-how to get NP in urology "CUNP"

Hi, I am considering going back to school to get my NP and was considering among many options possibly working as a urologic nurse practitioner. As of now I have my BSN RN and have worked on a med-surg/oncology unit for 2 years. So do I go to a general NP school and just get a job with a urologist, or are there specialty schools for urologic NP's? I have been trying to find out info online and have had no luck on anything specific at all. I am looking for some direction to get me on the right path for this career move. Thanks for any and all help you can give!