As to the observations about the conquest of the Nahua (Aztecs), I have to say that while technological superiority can have a short-term effect, it is important to note that 75% of the population of Tenochtitlan died of smallpox during the siege. Many of our ideas about how much difference technology makes arise from North America's myth about itself. One could well argue that this belief in the power of technology from the revisionist histories of the Americas is one of the things that contributed to America's gross mismanagement of the Vietnam War. Arguments about the power of tech are best made using examples in which there was not another overwhelming factor, in this case a lack of resistance to European disease. (It finally paid off to be the filthiest people on the face of the earth

)
Nonetheless, I find the observations about obsidian intriguing, especially in light of the George Martin Song of Ice and Fire books.
All that stated, the real reason I'm posting to this thread is that I too am in need of some helpful pointers for materials and/or advce for a campaign I plan to start in about three months set in a primitive ice age society. Being very short of funds, I'm hoping that I can be pointed to resources that don't entail a financial outlay.
While it's fairly easy for me to envision the primitive weapons, equipment and economies -- anything where we have real-world equivalents, I'm having trouble imagining D&D classes into an ice age world in which people are struggling for survival. So far, I've decided to get rid of the Fighter, Paladin, Monk and Wizard. It seems to me that Bards, Barbarians, Rangers and Sorcerors can basically be ported in without difficulty but I'm left with the problem of whether and/or how to include Rogues, Clerics and Druids.
While Druids initially seem a good fit for a primitive society, they seem vastly disadvantaged by the physical environment of an ice age, based on their spell list. Rogues and Clerics, on the other hand, seem to me to be very urban classes and I'm left wondering (a) how to modify rogues for a society without cities (b) how many rogue skills should be unavailable because of the non-urban nature of the campaign (c) how to culturally locate rogues. Clerics again, seem a very urban class to me but I find myself unable even to articulately express how they're unsuited to the environment I imagine. With the natural world in retreat, I'm essentially looking for some compromise between the Cleric and Druid classes. Attempting to create a divine spellcaster class is somewhat problematic; I'm reluctant to have a formal shaman class because there
may at a later point be an opportunity for a divine spellcaster to advance as a cleric and I don't want to force people to start again at level 1 because they're then forced to multi-class.
Anyway, any and all advice is appreciated.