| You can try sites like Adoption.com that have lists of adopted children and birthparents with hopes of making a match.
You enter all of YOUR information,and any info you have about your bio-mother, and at some point if there is a match, you can be contacted.
The one concern I have here, though: WHY are you searching for your biomom? If you were in foster care, it's usually for a reason like neglect or abandonment. Are you ready to deal with rejection if your biomom doesn't want anything to do with you?
Similarly, are you going to be okay if you do NOT find her?
You can check with the foster care system, check with adoption agencies, and check court records in the city where you were adopted, as other avenues to search. | 
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