Who do I talk to about my daughter seeing a black shadow person. To find out what it is or why she is seeing this.

Explain why and how shadows are made. Explain that many times we image things so much, they seem real.

I would take her to church, it might not be any thing more than her eyes playing tricks on her , but if it truly is upsetting her then it would not hurt to ask a minister or a pastor some one who not only has a background in psychology but also has knowledge in spirituality and the religious realm to talk to her.

What?

I'd have her eyes checked to rule out any issues. As a teacher, it a amazes me to see how many children see shadows or dark spots. After a checkup, they end up in glasses.

Children are well known for having VERY active imaginations... which are really a good thing when they are still small... not so much when they grow up.