0-60 I would recommend affliction for minimum downtime.

If you go to wowwiki and look up warlock talents they will have affliction builds for you.

At 60 I would recommend swapping to a felguard demonology build, for a few levels till you've got some spell damage built up. There seemed to be a leap in the toughness of mobs between azeroth and outlands (But I was soloing and had stamina gear instead of anything with spell damage on it)