A bit of bogus info in this thread so far.

First, Greydwarves do NOT spawn by you making sounds. Those that have spawned are attracted to the sounds you are making.

Second, Greydwarves rather easily drop aggro, and even line of sight if they get within range of fires/torches. In fact, if you lure one inside your house, it's extremely likely that it will remain un-aggro'd the entire time. You can even build structures around them and make them your base secretary or something. :P

There's several ways of dealing with them. Make a wall (Roundpole fencing, Core Wood Beams, Stakewall, earth wall, stone wall, trenches, whatever) around your entire base. Then plop down some crafting benches so that every area inside the fencing is covered. You can later replace some of these benches with campfires if you want. That will stop them from spawning INSIDE your base.

Now, as long as you are not near the walls, you really won't have to worry about anything except occasionally going around repairing your walls and fighting stuff when you WANT to, instead of having to deal with it every 2 minutes.

Another way is to make huge pits and drag some GDwarves into it. I'm not SURE on this fact, as I've never tested it myself, but there's supposedly a max number of normally-spawnable creatures, and if you surpass that limit by having them already spawned in a pit, then you won't get more.