Components come into the world in five major ways:
Existing items may be salvaged for components. This can be done using either a salvage kit or by taking the item to be salvaged to the appropriate crafting facility. The salvage kit will be consumed by use, but allows the user to use the quality of the kit, instead of their own skill, to determine the maximum quality of the component gained through salvage. Additionally, the components salvaged will be easier to carry than the items salvaged. In a crafting facility, the character's skill and quality of the crafting facility determine the maximum quality of components salvaged. Salvaging an item will not return all components used in its manufacture. In addition to reclaiming player-crafted goods, creatures and NPCs that use gear may drop damaged or otherwise worthless gear which can be salvaged for useful components.
Some enemies drop some type of raw component. Magical creatures, typically drop "remnants" that can only be collected by players with the correct knowledge skills, and which are useful in enchanting and alchemy. Other creatures may also have useful leather and meat available to players with the right skills.
Harvesting nodes will appear throughout the world, and players with the appropriate profession skills can interact with them to acquire a small amount of components. For some nodes, this may require the player to have a particular harvesting tool. The resources and quantity available will vary from hex to hex.
Gathering nodes will often appear in hexes. Placing a gathering kit of the correct type near the node creates a storage object and some gathering camp. Over time, the storage fills up with components that can be removed and carted off, depleting the supply of that resource. Creatures are drawn to active gathering operations. These creatures will generally try to attack players in the area, but will destroy the gathering operation if no one is around.
For salvaging and looting, quality level is based on the creature's rarity and threat. For harvesting and gathering, quality level is based on the hex location and how depleted it is. A vein of quality 200 metal is much rarer and more valuable than one that's only quality 100, and quality 300 components are extremely rare.
When you salvage, collect, harvest, or gather, your skill bonus (or in the case of salvaging, the quality rating of the field salvage kit) also sets a cap on the quality of the components recovered. A character with a 150 bonus to his mining skill reduces a higher-quality vein to quality 150 ore, but would get the full 100 out of a quality 100 vein.