I googled for you (Love this site!!):
http://tinyurl.com/35c7y33
There are nine NPC chapters and four NPHC sororities, as well as 16 IFC fraternities, five NPHC fraternities, and (according the WIKI) one Native American fraternity and one Native American sorority.
According to the school's website, 7.29% of the student body (almost 1400 students) is represented in the 36 chapters on campus.
To find out details on NPC recruitment, you might try contacting the Panhel Recruitment Director:
http://www.ecu.edu/cs-studentaffairs.../npc/index.cfm