About Nebaioth .
- http://www.mechon-mamre.org/p/pt/pt0125.htm#13 Genesis 25:13
Nabit's descendants are Nubti (Nabatean). They resided in Northern Hijaz where Batra' as the capital.
The Ansar (Aus and Khazraj) were also from Nabit.
Bible Verses that Refer to Nebaioth:
These are the names of the sons of Ishmael, listed in the order of their birth: Nebaioth the firstborn of Ishmael, Kedar, Adbeel, Mibsam,
so he (Esau) went to Ishmael and married Mahalath, the sister of Nebaioth and daughter of Ishmael son of Abraham, in addition to the wives he already had.
also Basemath daughter of Ishmael and sister of Nebaioth.
1 Chronicles 1:29
Descendants of Hagar These were their descendants: Nebaioth the firstborn of Ishmael, Kedar, Adbeel, Mibsam,
All Kedar’s flocks will be gathered to you, the rams of Nebaioth will serve you; they will be accepted as offerings on my altar, and I will adorn my glorious temple.
Genesis 25:13 - http://www.mechon-mamre.org/p/pt/pt0125.htm#12
First born son of Ishmael. Considered the proto-ancestor of the Northern Arabs. See also http://en.wikipedia.org/wiki/Adnan and http://en.wikipedia.org/wiki/Islamic_view_of_Ishmael