TBC Classic is a faithful recreation of the original release of World of Warcraft: The Burning Crusade. Below you can find profession leveling guides for every profession and farming guides to help you gather materials you may need for your chosen professions.
Alchemy
Blacksmithing
Enchanting
Engineering
Jewelcrafting
Leatherworking
Tailoring
Herbalism
Mining
Skinning
Cooking
Fishing
Fishing and Cooking
First Aid
Lockpicking
Felweed
Dreaming Glory
Terocone
Ragveil
Nightmare Vine
Netherbloom
Mote of Fire
Mote of Water
Mote of Earth
Mote of Air
Mote of Shadow
Mote of Life
Mote of Mana
Knothide Leather 
Fel Scales
Nether Dragonscale
Wind Scales
Cobra Scales
Fel Hide
Thick Clefthoof Leather
Fel Iron Ore
Adamantite Ore
Netherweave Cloth