We adopted 2 boys at birth in Florida, now ages 7 & 4. They are the light of our lives.
We used a non-profit agency in Winter Park (near Orlando), http://www.lifeforkids.com/. Our first took 10 months, not much different than having a biologic child. The cost was the same or less than international, including travel. Our agency also provides financial assistance to adoptive parents in need. Lots of paperwork and home studies necessary to insure children are placed in loving, capable homes. Think of the tragedy for both a child and it's birthparents if placed in a negative environment.
If you adopt in the US, I believe an important question to ask your attorney or agency is "What services do you provide to birthparents". All are required to provide counseling. However, do they give equal weight to the choice to parent vs. place for adoption. It's important for the birthparent(s) to fully consider all their options including support for a parenting decision. Our sons' birthparents made a selfless, loving decision but only after fully considering their ability to parent their child. Make sure your attorney or agency doesn't just provide lip service to a parenting choice. We only wanted to adopt in a case where the birthparents truly didn't believe they could parent.
Our adoptions were both open. We provide a letter and pictures twice a year. We have no other contact. It's important for birthparents to know their child is healthy and happy. We only fear the unknown.
We haven't adopted internationally but have friends who have and they also have wonderful families as a result. We also have friends who adopted US tweens/teens - they are also positive examples of a family blessed. In the end, it's your family's decision to do what feels right for you. All your choices have hoops to jump through and ups and downs but that's life - enjoy the ride!
If you have any quesitons, feel free to contact.