Hah, I bought a home built in 1913 a few years ago and am also having to deal with the same shit, but not quite as bad as yours sounds. Bought it at an auction and picked it up dirt cheap...have already received offers to mortgage it for 3x's what I paid for it! It was brought up to code in '97 so all the electric is new but I think the electrican must have done the plumbing too! My only real problems with this place is the bathroom plumbing. The shower only trickles out while the bathtub spout works fine for about 4 minutes then it too slows to a trickle. I get around it by siphoning from the nearby sink to fill the tub but eventually and soon will have to gut and replace the bathroom pipes along with the tub, sink and toilet. But until I can save up the funds for it I'll continue siphoning from the sink...lol
Other than that it's a great house and what's even better, it's fully paid for!