extra-solar navigation

I just read an online discussion of StarGate navigational mechanisms, specifically the inconsistency of having a six-point destination coordinate and a single point of origin. The conclusion was that it's basically silly, unworkable, and functions only as a plot device. It made me think, though, about the underlying issue.

This is not an uncommon subject in science fiction. There are many, many stories which revolve around navigational difficulties, finding and obtaining star charts, or getting lost in space and trying to find some known quadrant in order to go home. Some of that is simply updating the traditional lost at sea tales of our pre-satellite navigation past, but some of it is a real issue.

Obviously, while we're still within the Solar System, we won't have too much trouble. Fairly standard telescopes and computation will tell us where each of the known atronomical bodies - including Earth - will be at any given point in time. But what happens outside our star system? What happens when we're far enough away from our star that the constellations no longer look familiar?

Will each ship's computer need to be able to model in four dimensions (time being a significant factor in these calculations, especially if we have to consider relativistic time-shift, or long periods such as would be experienced by generation ships or ships whose crew were in some form of induced hibernation) to location of every star in the galaxy? Every star within the home galaxy and every star within the current galaxy, as well as the relative location of every galaxy in the universe..? That is a computationally massive task.

How else could it be done? Are we doomed to the science fictional future of lost maps leading to lost star systems and worlds?