Beyond asking those you know for recommendations, here are some listings of agencies you can use to begin your research:
Christian Alliance for Orphans is a great resource to utilize in searching for an adoption agency. Click on this link to learn more! http://www.christianalliancefororphans.org/agencies-and-ministries/adoption/
National Foster Care & Adoption Directory Search – The National Foster Care & Adoption Directory (formerly the National Adoption Directory) offers adoption and foster care resources by State.
Adoption Service Provider Search – These adoption service providers have been accredited or approved by the Council on Accreditation (COA). Only those adoption service providers who have been accredited or approved by the Council on Accreditation will be able to provide any of the defined adoption services for Convention adoption cases (unless an organization or individual is operating as an exempt provider or under the supervision of an accredited or approved adoption service provider).