Since the Start of the Great Recession, More Children Raised by Grandparents, Pew Research Center, 2010.
http://www.pewsocialtrends.org/2010/09/09/since-the-start-of-the-great-recession-more-children-raised-by-grandparents/

AARP Grandparent Information Center: a variety of resources for grandparents.
http://www.aarp.org/relationships/friends-family/

A Family’s Guide to the Child Welfare System: A guide for families in the child welfare system, including experiences of other families, laws and policies, and how to advocate for a family's rights. Also available in Spanish.
http://www.tapartnership.org/docs/familyGuideToChildWelfare.pdf

Grandfamilies State Law and Policy Resource Center: from Casey Family Programs, the American Bar Association Center on Children and the Law, and Generations United, this searchable database of current State laws and pending legislation in support of grandfamilies, and assists policymakers in exploring policy options to support relatives and the children in their care both inside and outside of the child welfare system (2012).
http://grandfamilies.org/

Grandparents Raising Grandchildren Resources: from USA.gov, this collection of resources for grandparents includes information on benefits and assistance, health and safety, and state-specific information.
http://www.usa.gov/Topics/Grandparents.shtml

Kin Caregivers and the Child Welfare System: a Factsheet for Families from the Child Welfare Information Gateway (2010).
https://www.childwelfare.gov/pubs/f_kinshi/f_kinshi.pdf

Guardianship is another type of permanency whereby a child gains the legal security of a guardian and is removed from the administrative responsibility of the child welfare system if the child is in foster care, but the process does not require termination of birthparents’ parental rights. Subsidized guardianship enables those becoming guardians of children in foster care to receive a monthly subsidy to assist with the child’s care. The Fostering Connections Act allows states to use federal funds to support subsidized guardianships. The number of youth leaving foster care through guardianship has increased since FFY 2000 when 9,043 children (3%) did so. By 2009, guardianship was achieved for over 19,000 children, or 7% of those who left care that year (AFCARS). 

For the most recent figures, see AFCARS reports:
http://www.acf.hhs.gov/programs/cb/research-data-technology/statistics-research/afcars

Subsidized Guardianship – Summary and Analysis, Grandfamilies.org
http://www2.grandfamilies.org/SubsidizedGuardianship/SubsidizedGuardianshipSummaryAnalysis.aspx

Increase Exits from Foster Care to Permanence through Guardianship. Center for the Study of Social Policy. Policy For Results:
http://www.policyforresults.org/child-welfare/increase-exits-from-foster-care-to-permanence-through-guardianship

Research on Benefits and Outcomes of Subsidized Guardianships:
Never Too Old: Achieving Permanency and Sustaining Connections for Older Youth in Foster Care, July, 2011, Donaldson Adoption Institute, pp. 42-48.
http://adoptioninstitute.org/old/publications/2011_07_21_NeverTooOld.pdf

Subsidized Guardianship: Testing the Effectiveness of an Idea Whose Time Has Finally Come, May, 2008, University of Illinois Children and Family Research Center.
http://www.nrcadoption.org/wp-content/uploads/Subsidized-Guardianship-Testing-Effectiveness-Testa-2008.pdf