One question many adoptees ask is: "Why?" To answer that question they are using whatever means necessary to contact their birth parents. There is even a television show based solely on a gentleman who works to reunite adopted children with their birth parents.
Assemble all information you have on your birth parents. If your adoptive parents are cooperative they should be able to give you a little bit of information or at least be able to tell you where you can find a social worker who could help you. If your parents are not cooperative you might be able to visit your local social services office to seek out the social worker who was responsible for your adoption case. If you are younger than 18, a social worker is unable to assist you in your search without direct permission from your adoptive parents.
Visit or contact a social worker, or your own social worker, who can help you find out more information on your birth mother. Unfortunately many times birth mothers sign for closed adoptions and wish to keep all of their information hidden. If this is the case your social worker will be unable to give you any contact information, or give you very little.
Use little bits of information to make your own search. If you have an original copy of your birth certificate, you might be able to find out the name of your birth mother. Write down any information that you can find about your birth mother. You also might be able to trace your birth father to find information about your birth mother.
Use the Internet to visit adoption sites. Some sites offer reconnection services for a fee. Enter all the information you know about your birth mother onto the site's forums, and leave your contact information for others in case they have any information.
Prepare for a reunion. When you have obtained enough information to contact your birth mother, make the decision on how you want to make first contact. You may wish to make a phone call or meet in person. You will not know the kind of situation you will be walking into. You might greet a birth mother who chose to place you in an adoptive home to offer you a better life, or you may find a birth mother who gave you away because she didn't want you. Be prepared for the different things you may hear.
Bring someone with you, even if they stay out of the way until you leave. You might need their help and support.