so far my fiance has done 3 guided tours for graduate school in which he received info packets, talked to current grad students, teachers & counslers which was helpful. he will be applying to his top 5 choices (due to competiveness with grad schools) we booked his tours in advance about 1 month or more out & had no problem with getting an appt. , although most grad schools only offer campus/program tours once a week.
we based his choice for grad school on school programs & availability-class size, additional resources (like internship, residency oppurtunities) cost of annual tuition & fees, surrounding area statisics (like cost of living - career oppurtunities & home purchase costs, safety ratings) and to do's (recreation, transporation-airport) and also asked his current college counsler for suggestions.
best of luck with your college plans!