Grandparents Raising Children Support Group
This community is dedicated to grandparents who are the primary caregivers of their grandchildren. In cases where the parents are not willing or able to provide adequate care for their children, grandparents may take on the role of primary caregivers. Join the support group to find support, share your experience, and get advice from other members.
http://az.gov/services_famhealth_children.html
I looked at it and there is a lot of info on children and family services for you to follow. Hope this helps.
You could find out for sure on any of the many adoption sites. They may also be able to help you with some of the other issues and questions you or hubby may have about adopting the gc.
There are actually several adoption support groups that are quite active right here at DS that would probably be able to answer a lot of your questions about that aspect of things.