It's a little late in the game, but the Black Gulch is a good area to farm titanite chunks and large titanite pieces. The best part is, there is close to zero risk of you dying from this, once you get the hang of it.
Shoot the black tar pits with a fire arrow, and the creatures will die from fire. When they are dead, run up, collect items, and repeat. Use a bonfire Ascetic at the first bonfire, to get the mobs to respawn. You can shoot at the tar pits a little after the first bonfire. If you use a bonfire Ascetic at the second bonfire, the boss will respawn, but not the mobs.
To farm the second area, stand at the exit of the second bonfire, and you can ignite the 5-6 tar pits quickly and easily. Best part is, when you replay it in NG + later games, this will not make the area significantly harder, because you can use the same cheesy tactic, to take out the mobs, without danger to yourself.
This will also net you quite a lot of souls. Remember to equip the Jester's cap: http://darksouls2.wikidot.com/jester-s-cap + Covetous Gold Serpent Ring: http://darksouls2.wikidot.com/covetous-gold-serpent-ring
Torches can be found in various places around the game world as items. In addition, enemies that carry torches (there is one on one of the bridges in the Hunters Copse, and a few more in the Gutter, to name a couple of places) have a high chance of dropping a torch upon death.
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Titanite Shards can be looted from the large, green Steelworker Undead at lower Earthen Peak, as well from as the peasant villagers in upper Brightstone Cove Tseldora. Also, one skeleton warrior in Harvest Valley, resting his bones in the same cave as Gavlan, has a very high drop rate for titanite shards. Once you have cleared Iron Keep, Stone Trader Chloanne will sell an unlimited number of Titanite Shards for 1,000 souls each.
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