I understand that well before writing the Koran, Mohammadrecognized
Allah as the "true one God, the God of Arabs, Christians, and Jews." 
(See the 'Story of Islam' - ISBN# 1-55607-722-6) At this time I have
read that he even prayed toward Jerusalem.  He then either traveled -
according to one source - or was conveyed by Gabrail by another source
- to Jerusalem where he wanted to become the prophet of the one true
God to the arabs.  The jewish priests rebuked his requests after which
he began to pray toward Mecca and subsequently wrote the Koran.  Where
can I find an authoritative source and early history of Mohammad
during this time?  I am not interested in the religious dogma or
devine guidance stories, just whatever historical factual sources may
exist.

My friend, if u need to learn about the early history of the prophet , u may read 

1. The Life of Muhammad: Translation of Ibn Ishaq's Sirat Rasul Allah

the earliest extant work on the prophets biography

http://shop.store.yahoo.com/talkislam/b3828.html

Cheers

Erhan