Probably not what you are looking for, but Theodolite HD turns your iPad into a surveyer's tool. Along with a tripod and survey stick you can do most things a surveyer can do, providing you know how to do those things, and with the caveate that it probably isn't quite as accurate as profesional tools.
There is an iPhone version too, which is probably the easiier to use.
I've used MotionX's GPS HD app to plot corners of a property using waypoints. If you have accurate GPS coordiantes for the property you could probably do that, then use a screenshot and somethjing like Skitch to draw boarders. I'm not sure how useful that would be.
Nothing else comes to mind.