As someone who has worked with hundreds of families I know several who have adopted.
There also seems to be a trend in the Bible - those who God has placed an extra special calling upon - are often adopted. I am not interested in debating or talking about that point, just that it is an observation.
Most of the families I know who have adopted would tell you it was a wonderful, very rewarding experience. I do know of two families who said it was a horrifying experience and nearly ruined their marriages. As you can imagine, these two cases were due to very special needs children. One who was truly psychotic and another who had severe learning issues.
My take on adopting - If God is calling you to take this action, then by all means follow Him and His calling!! If you are wanting to adopt for any other reason, stop and seek the Lord for His will.
Do you have any specific questions?