5) Are any Community Health Centers currently utilizing VistA?
From VistApedia
American Samoa's LBJ tropical medical center is using VistA. Recently the Samoa Department of Health became a divison on LBJ's VistA server which means that all of the health care in Samoa is no Vista.
In Hawaii there are 3 clinics using VistA
The state hospitals in Kauai and Hawaii are going to use Vista this year.