You should try African Presence in Early Asia by Ivav Van Sertima. I know it has a bit in it about palestine but I'm not sure if there are any specifics about mesopotamia.

If that fails, look up Runoko Rashidi's site as he is one of the leading authorities on early asia and even if you are not looking for the African presence, there should be general info about the area in his many articles (in which he often writes huge bibliographies)

His e-mail address also appears on his site and you should be able to e-mail him. He's one of the scholars who will reply to you if you e-mail him and he should give you a long reading list if you should need it.

The GLOBAL AFRICAN PRESENCE - Articles by Runoko Rashidi

that's his site.

Good luck.