Recently made a lock alt as was typically bored, and discovered how fun they are in terms of macros, so I decided to go a little insane with this one. In order to use it, you'll need one of two addons. Either Super Duper Macro, a very simple one to use that breaks after you hit the 255 limit in a way that it no longer displays the tooltip, or Macaroon, a pain in the ass to get used to addon that still gets the job done.
You'll probably understand it but basically, if you've no pet it has modifiers to summon different pets. No modifier to first cast Fel Dom. With pets up, the macro changes based on which one you're currently using. With void, either consume shadows or sacrifice. Succubus, seduce. Felpuppy to spell lock, dispell you or remove enemy buffs.
/cast [modifier:ctrl,nopet] summon voidwalker
/cast [nomodifier,pet:voidwalker] sacrifice
/cast [modifier:alt,pet:voidwalker] consume shadows
/cast [modifier:shift,nopet] summon succubus
/cast [pet:succubus] seduction
/cast [nomodifier,pet:felhunter] spell lock
/cast [modifier:alt,pet:felhunter,target=player] devour magic
/cast [modifier:shift,pet:felhunter,target=target] devour magic
/cast [modifier:alt,nopet] summon felhunter
/cast [nomodifier,nopet] fel domination