In ancient times I could have helped.
Seriously, I had a brief time where I was pursuing that area in my studies, that ended somewhere in my second year of college and was only briefly revisited in about 1980 with a few courses at City College in New York when I was temporarily unemployed. Subsequent years I for whatever reason disposed of every one of the books related to that time, there were some which harked back to early times.
Have you considered contacting a Yeshiva or the like? They might well be able to set you on an accurate path or through archaeological and anthropological studies at local colleges/universities, which while may sounding far fetched, would place you in contact with books and texts of ancient cultures and how their belief systems came to be.
Keep in mind though that even texts such as Sepher Yetzirah (which many regard highly) in our current form has been translated many times over so while technically factual, there will be a touch of human involvement, thought process. History is kept and listed by man, and man does not always want to acknowledge all that has happened and will delete that which does not agree with them at the time. Perhaps that is why we find one set of facts in one part of the world and a moderately or significantly different set in another part.
Keep an open mind (which I sense you already do) as you travel and explore.
(If I am going too far off into incorrect direction, let me know and I will gladly stop)