There was some discussion here before on soundproofing between semi D houses, I think Father Dougal might have done this before (if memory serves). I cant seem to dig it up here though (the search did work well as opposed to ezboard)
I bought a second hand property because I had expierance of noise from next door renting a house a few years old thankfully the house I have bought now is solid block laid on the flat between the houses yes peaceful and at least you can hang a picture without having to search for a stud in a partition.
Speaking of which if anybody needs a stud to hang pictures call me
Sweeet