I can't speak for the Inca or Maya, but I can talk about the Triple Alliance with a degree of certainty.

The Aztecs made very, very heavy use of obsidian in edged weapons, in the form of spears, daggers, arrowheads, and macahuitls (Wooden "swords" ringed with obsidian chunks, designed to be easily replaced if broken). Their armor was typically wooden and leather/hide-based, as well as making use of thick cotton jackets (Mayan version of these were soaked in seawater to be even more durable, and so impressed the Spanish with their durability and lightweight/breathable qualities that many of them abandoned their steel armor for cotton).

If you were a commoner, your weaponry was often mass-produced and provided by the state in a Triple Alliance city. You were given a spear, maybe a shield, and that was pretty much all you got. You hadn't earned the right to be a member of the Warrior class, so you didn't get the good stuff. Anything else you had you brought from home, which may be an obsidian dagger, club, or sling. They also did make use of slings, atlatls and bows, but these were often used as skirmishing units to harass flanks and defend fixed positions - they were not the main assault force of an army, and so were used by the less-desirable troops on the outskirts or behind the front ranks while the real warriors got in close for the kill. It is worth mentioning, however, that Aztec slingers were quite effective, and considered a very valuable military asset to any Aztec commander due to their rate of fire, easy training, and dirt-cheap (literally) cost to arm and equip.

The Warrior classes, however, were equipped by the state through high-quality craftsmen, and also allowed many other personal embellishments that they could get done. They were given wooden and cloth armor to wear, with wooden helmets (in the shape of a Jaguar or Eagle depending on which particular warrior brotherhood you belonged to), adorned richly with gold, quetzal feathers, and other symbols of power. Brave warriors who had consistently proven themselves on the battlefield were often given a jaguar skin to wear draped across their skull and back, to show their martial prowess and their ability to cheat death and emerge victorious. They were armed with macahuitls, spears, and shields draped in animal skins and feathers. These guys made their entire living killing on the battlefield and in taking sacrificial prisoners of war to slaughter at the tops of the Temples of Huitzilopotchli and Tezcatlipoca. Their enterprise was funded by extremely skilled state craftsmen, but many successful warriors would have personal weapons made for them, with generals and other high-ranking members would have a craftsman be their own personal armorer who worked exclusively for them.

Standards for these warriors was pretty high - you were expected to obey your commanders at once, and to be proficient in the tactics your units were instructed in. Commoners were put through basic spear drills, and expected to fight as essentially a giant human meat grinder against other common troops. Elite units were trained to be hard-hitting shock troops, who would make or break a battle line, winning glory for their city by routing the foe at their weakest point. The weapons they used were quite standardized (Macahuitl, spear, and shield) not just because it was demanded of them, but also because being able to wield those weapons in battle was considered a privilege in its own right - why on Earth would you fight with the weapon of a commoner if you had earned the right to fight with the Macahuitl?

War was a business to the Aztecs, and they treated it as such. If you were a commoner, you got the bare minimum and were herded into battle to bring glory to the REAL warriors, who got the high-quality arms and armor.

As far as I am concerned these civilizations were quite different and hundreds of miles apart so maybe you should narrow down your question a bit? Maybe someone competent will answer then