I completely understand you predicament, liblue. I've been in that situation before and tried speaking very politely to my offensive neighbor on many occasions with no successful results. Eventually I had to move, hopefully you will have better luck.
The only advice I can give you for initiating this discussion is to avoid writing a letter if possible. It would be a good way to organize your thoughts before speaking to your neighbor, but if it's the first and only form of communication you have with him it may may backfire. Attempting to get him to understand your point of view
might give you positive results. If not, you can move on to blatant guilt trips followed by more drastic measures if necessary. Once you have spoken with your landlord there is no going back. Proceed cautiously, one step at a time. Step one, come up with a plan weighing pros and cons of your actions while taking into account the response a sane person might have. Don't assume to much about this guy, he might not have a clue how much this bothers you.
