emsy, everyone has given you excellent advice. It's now your turn to do some leg work. Go to your future school's website, and look up the Greek Life section. It may be hidden under a lot of other names, such as Student Life, Student Activities or such, then to Greek Life, or Sororities. Some schools, but not most, will link you directly to each separate chapter.
From there, make a list of the sororities at your school, then look up
their national website. Chances are that the site is something like
www.sororityname.org.
Check out the philanthropies, the goals, the ideals that each of the sororities has on a national basis. Note the photos, the graphics, the mascots, the history - and realize that they are trying to put their best foot forward.
Then, attend all Recruitment Seminars or such, and
go through Recruitment! You're not going to get any idea of who's special and who isn't from anywhere else but your heart.
Best wishes on a successful Recruitment.