WHAT OPTIONS DO I HAVE TO BECOME A REGISTERED NURSE?

I HAVE ALREADY COMPLETED 4 YEARS OF COLLEGE AND I HAVE A BACHELORS DEGREE IN SOCIOLOGY. MY INTENTIONS WERE TO START TAKING GRADUATE COURSES IMMEDIATELY TO GET MY MASTERS IN EDUCATION; HOWEVER I HAVE CHANGED MY MIND AND NOW WANT TO BECOME AN RN. I AM AWARE THAT THERE ARE A COUPLE OF SCIENCE COURSES I MUST TAKE AS PRE-REQUISITES FOR THE NURSING PROGRAM. HOWEVER I AM WONDERING HOW LONG IT WILL TAKE ME TO BECOME A NURSE? AND HOW SHOULD I GO ABOUT BEGINNING SCHOOL FOR NURSING? ARE THERE PROGRAMS OR WILL I HAV ETO GO BACK TO COLLEGE FOR FOUR YEARS?