Hi Summer... I would recommend the book Attachment in Psychotherapy by Dr. David Wallin. It's available on Amazon. It is a little technical but not so much as a lot of research articles. What he did was take much of the current research and put it into book form as he said HE couldn't find a book on this subject. He takes you from an introduction into attachment theory (Bowlby, Main, Ainsworth) into what is happening today. He talks about some case histories and he discusses mindfulness, the connection to the body, and trauma. I find myself going back to this book time and time again. It was money well spent.
TN