Because I feel like posting something useful now and then - a quick overview to crafting professions (note: limited - so far - to the "while leveling" stage with no regards to the endgame).
Basically there are three gathering professions (foraging, butchering and mining) and you'll gain raw materials from "adventuring" as well (cloth and rare crafting ingredients). There are 6 manufacturing professions (armoursmith, weaponsmith, outfitter, apothecary, artificer, runecrafter).
Armoursmiths craft mail and plate armour and require metals and hides. The profession goes well with mining and butchering.
Weaponsmiths craft all weapons except for staves and wands (including bows, yes). The profession goes well with mining and foraging (bows come from wood which is picked off the floor by foragers).
Outfitters make leather and cloth armour and require cloth and hides (obviously). Goes well with butchering (also obviously) and I have not seen anything that requires a second gathering profession so far.
Apothecary makes potions (including healing and mana), buff potions, AoE attack and healing bottles (called philters) and dies. It requires both foraging (for the herbs) and butchering (for animal parts - lots of animal parts).
Artificers makes wands, staves, necklaces, rings, and offhand items. Magicy stuffs. It needs mining and foraging for wood and metal and gemstones.
And the scary one:
Runecrafting. This makes enhancements that can be applied to anything (armour and weapons alike). It requires magic items to be broken down. Not to fall back on the lingo of another game, but enchanting requires disenchanting items. This is also an incredibly painful profession to level, due to the relatively complex resource system and the sheer amount of things you need to break. If you want to go for this, I'd combine it with outfitter and butcher - just so you can craft loads and loads of cloth shoes to disenchant (err.. runebreak) for raw materials.
The good news: None of the crafting professions have a minimum level to learn. You'll gain skill in bunches of 75 (Novice to 75, Skilled to 150, Expert to 225 and Master to 300). If you feel like starting your "main" character with all three gathering professions, there is nothing to stop you from sending it all on to your low level alts and having them craft.
One hitch with this plan: The crafting dailies.
In each of the two capital cities is a little person (disclaimer: as shown from horseback - I have no idea how tall he really is. Or if he's a she. Or if he actually lives there. Or she. Or ... wait.. what was I getting at?) that hands out crafting dailies. The reward are a few tokens - more for the harder ones. Those can be used to buy rare patterns. In Sanctum you can find the little bugger (err.. buggeress and she's probably tall as well.. possibly) here:
And where do the quests go? That's the problem: They are delivered into a base camp. Depending on the level. The first ones go to Quicksilver College in Silverwood (if you are a Guardian - Defiants are cunning and can find it on their own. Please? Don't hurt me?), the later ones go to higher level areas. And this is where the low level alt would struggle. Delivery might be hard. Real hard. I still don't know how to get my level 27 Paladin to the Draughtlands.
Oh and .. are the items worth it? Possibly.
It depends on the profession. I found armour to be the weakest of the things to craft. Quest rewards are plentyful, drops are common and you'll likely find something equivalent to wear before you reach the required level. Blue crafted things (those made after buying the daily quest patterns) are a different story completely. They are amazingly powerful.
Weapons are slightly better. Especially the ranged ones are something harder to come by.
Rings and Necklaces I found generally a pain to find, so I suppose the crafted ones are good. I ... err... didn't actually make an artificer yet, though, so I couldn't say.
The potions are a true lifesaver. If you only have one character to start with - make it an apothecary. You'll never have enough healing potions and they do begin to get expensive. On the bright side - you can buy them from NPCs.
And runecrafting? Well there is nothing comparable (Disclaimer: Not actually true - some of the faction vendors sell "enchants") within easy reach. This will make all of your items more powerful.
But the resources: There are kinetics (1 burst = 3 charges = 15 arcs), perpetuals (1 flare = 3 glow = 15 blur), and sentiences (1 blast = 3 surges = 15 sparks). There are powders and shards (uncommon and rare: both are transformed at a rare of 1 crystal = 3 shards = 9 powders) and you never get any of the type you need. Mark my words! *shakes fist*
Final note:
Outfitters make bags from cloth. This might factor in.
