If you want something like this:
Building A - 15 APs - VLAN 1
Building B - 12 APs - VLAN 2
Building C - 13 APs - VLAN 3
Then you can accomplish this with zones. Each building is assigned a zone, and each AP in that building is configured for that specific zone.
If you are trying to do something like this:
Building A - 15 APs - 4 users on VLAN 1, 3 on VLAN 2, 10 on VLAN 3
Then you will need to either know the MAC of all these devices ahead of time and manage that, or you can deploy Clearpass as Colin mentioned.