yea 19's are still prety good
i'd play your warlock very viable good damage as well as cc really strong class atm
if this is yours Bromode @ Azgalor - Community - World of Warcraft
i dont think you need much new gear boa pants i think the 3.5k jp staff ist bis not sure also enchant ur bracers w/ sp
Definitely play your lock (destruction spec) unless you enjoy resto shamans.
There's not really any new gear you need to look into, although you do need a few changes in your current gear on your lock. (assuming that is your lock linked above) Try to get hit capped and swap a few enchants as well. You can use my armory in my signature if you need a BiS set to look at. There's also a few in Pizzas Armory Thread as well.