If they're not housed (I don't know if Chapman is) then "dropping by" becomes super difficult. The chapter president, vp and new member ed (different groups have different names for the positions) are the women you would ideally speak to about this. You may also want to try to contact the Greek Advisor and Panhellenic VP Recruitment. If worse comes to worse, you could hang outside a Panhellenic council meeting and wait for the chapter president afterwards.
Of course if you come off too overzealous it could seem stalkerish.