Sources: OctoWow DB + Wowhead Classic. One row per recipe. Every way to get it (vendor, reputation vendor, trainer, quest reward, drop) is listed one per line.
Vendor and recipe links go to Wowhead Classic. Purple links = only exists on OctoWow, so it links there.
Faction: Alliance / Horde = friendly to that side. Neutral = neither side hostile. Quests show the side that can take them; drops are open to both.
Source: Vendor = sold for gold, Reputation = sold by a vendor but the recipe needs faction standing (shown in the Reputation column), Trainer = learned from a profession trainer, Quest = quest reward, Drop = looted from creatures or containers. Recipes that need reputation only appear while the Reputation source is ticked. A recipe with many sources shows the first few; click "+N more" to expand. Routes only use sources with a known map position (vendors, trainers), never drops.
Rarity = quality of the crafted item (enchants have none).
Disenchant columns (Tailoring, Leatherworking, Blacksmithing, Engineering): iLvl and rarity of the crafted item; mats derived from the crafted item's quality and item level (the ilvl stat, not the required level) using the WoWWiki disenchanting tables. Percentages are the chance per disenchant; "×" is the quantity range. Soulbound or special items that cannot be disenchanted in-game are not flagged. "-" = crafted item unknown.
Routes are estimates. The map positions, flight paths, boat and zeppelin times in this page are a hand-built model, not game data.