Able to learn at level 5, skills 1-300 are learned from charming trainers in any major city in Classic WoW. Above that, Trainers will be in Honor Hold for the Alliance or Thrallmar for the Horde, both located in Hellfire Peninsula. Grandmaster training at 350 will be available to players at level 65 and will learn from Dalaran, which is the main hub of the Wrath of the Lich King expansion. For a list of all the recipes (or at least the cheapest ones to increase your level), it might be a good idea to get a more specific enchantment guide 1-450 for detailed information such as green recipes (rare) and the cheaper materials. to use to increase the level of the enchanting profession.
At very low levels, disenchanting rare or higher quality armor and weapon items can also level the enchantment skill. An important note when trying to level up the enchantment is that low-level enchantments can hardly ever be sold and can sometimes even be declined when given away for free. To that end, enchanters end up enchanting the same piece of gear over and over again to increase their enchantment level. For example, if enchanting bracers with 2 bonus strength is “Orange” and will guarantee 1 level of skill increase, the enchantress will simply enchant his bracelet a few times until the recipe turns yellow. Once yellow, performing the enchantment will not guarantee an increase, but only a high probability of level increase. If you are following a 1-450 step-by-step enchanting guide, you should take note of when a recipe “turns yellow” and no longer guarantees a level increase, as it will prevent wasted materials.
Leveling up your enchantment from level 5 is a good idea, as many of the quest rewards or dungeon drops may not be an upgrade for you and would typically be sold to a vendor. But instead, as an enchantment, you can disenchant those items and then reuse the materials to increase your ability to enchant. This disenchantment method also applies to items that are already “soul bound” to your character. Which would mean that if you currently have an item equipped but get an upgrade on that item slot, you can equip the new item and disenchant the old one, so more materials are provided. For more information on whether or not it is worthwhile to disenchant an item rather than sell it, I advise that you check with a proper enchanting guide for the prices of the items that you will get in exchange for disenchanting first. Additionally, most enchanting guides will provide locations on which enemies can drop rare recipes that affect how much gold you will be able to obtain once your enchanting ability is maxed out.
One of the perks of being an Enchanter is that at higher skill levels you can also enchant your rings which provide additional attributes. Also, if you have more than one character, you can enchant Inscriptors vellum to create enchanted scrolls that you can pass to different characters.