His PUBLICLY AVAILABLE registration information for his website, http://harunyahya.com, is as follows:
Administrative Contact, Technical Contact:
Publication, Global ms7uh6j58c5@networksolutionsprivateregistration.com
Global Publication
ATTN HARUNYAHYA.COM
care of Network Solutions
PO Box 459
Drums, PA 18222
US
570-708-8780
Record expires on 23-Jan-2022.
Record created on 23-Jan-2000.
Bulk whois optout: N
Database last updated on 23-Sep-2012 14:42:05 EDT.
Domain servers in listed order:
NS1.P03.DYNECT.NET
NS2.P03.DYNECT.NET
NS3.P03.DYNECT.NET
NS4.P03.DYNECT.NET
Both the address and phone number are fake (they apparently are the address and phone of Network Solutions itself. However you CAN sue Network soultions in small claims since they are now attached to his company. Sue them in small claims for damages and ask alternatively that they hand over all the information that they have on the person. Attempt to take over his website via court order in small claims (it's an asset).
There is also a Wikipedia page about the guy
http://en.wikipedia.org/wiki/Adnan_Oktar
Also: Some states allow injunctive relief (court order for youtube to take down the site) in small claims court and some do not. If your state does then file and ask that the site be taken down in addition to other damages.