THE CHEAP WOW GOLD:

  Since the release of World of Warcraft, you can choose only two primary professions, aside from having three secondary professions of fishing, cooking and first aid. So what two professions would be best for your DPS?
   Skinning, Herbalism and Mining don't give any added benefit to your DPS. While it can be said that having a profession like Herbalism will give you easier access to herbs for your alchemy, the same can be said for using gold to buy them off the Auction House. The only item in the game that requires Herbalism is Fel Blossom, which is pretty useless since it shares a cool-down times with a Master Health-stone.
Mining and Skinning are equally useless, and have nothing that is profession specific for them. Along with Herbalism, everything these three professions gather can be obtained from your alts, friends or the Auction House. It is true that some raids needs a miner in certain instances, but let someone else who is not DPS focused like you are have that job.
Wearing a Sorcerer's Alchemist Stone in a trinket slot, a Warlock can benefit from the Alchemy profession. This is a relatively new trinket as it was added in Patch 2.4.0, and it requires being exalted with the Shattered Sun Offensive.
To evaluate the DPS of this trinket, we'll have to assume we are chaining Super Mana Potions and determine how much of a benefit the 40% potion boost would be. We will also have to consider any DPS loss from not wearing a better trinket in that slot.
An average Super Mana Potion will restore 2400 mana and can be taken every 2 minutes. To convert this to overall MP5, we can do the math to determine that using Super Mana Potions gives an equivalent 100 mp5. However, with this trinket, the 100 MP5 becomes 140 MP5, so the benefit this trinket gives is +63 spell damage and +40 MP5. Now let's turn to our Leulier spreadsheet that tells us our DPS values for each point in these areas.
With blacksmithing profession, there is no gear or consumable that can be used by a Warlock.
With enchanting, the enchanter's only DPS increase is their ability to enchant their own two rings with Enchant Ring- Spellpower, which results in a total of +24 spell damage for 26.4 DPS. Only enchanters can enchant their rings. Note that you can drop enchanting after you enchant your rings and still keep enchants. It seems to be almost a loophole of sorts but it works.
The engineering profession gives some very interesting gear choices for Warlocks in all level of raiding. In general, Engineering provides profession specific head pieces. For endgame raiding, there is the Schematic: Annihilator Holo-Gogs that is a rare drop from Sunwell trash.
Jewel-crafting is another interesting option for end-game raiding. Basically, jewelcrafting will allow you to cut better epic gems that are BOP. Jewelcrafters are also able to craft profession specific neck pieces that are BOP. 
Leatherworking has taken on a life of its own for endgame raiding guilds with Drums of Battle. It's not a trinket, so it doesn't take the place of any gear. It uses a global cooldown, but since your trinket does not, you can put it in a macro to use it as a trinket to combine their effects. This little item of uberness gives 80 Haste to you and your entire party for 30 seconds. For the purposes of any on-use item or trinket, we convert this to overall use by diving the buff over its cooldown. So this is equal to a 20 spell haste bonus for you.
When the Burning Crusade expansion was released because of the three Frozen Shadoweave pieces, almost very raiding Warlock started out as a Shadoweave Tailor. Those pieces gave a huge head start when everyone started out raiding Kara. As they progressed, people eventually replaced all three of those pieces with better gear around the T5 level. There is one item left in the endgame that may breathe new life back into Tailoring. It is the Pattern: Sunfire Robe that drops off of trash in Sunwell Plateau.