If the guy is really creating a hostile workplace you need to document all over the top incidents, like making your boss cry. There are many legal ways to get him relocated. You need to start a good defensive position on his abuse. http://www.eeoc.gov/laws/types/harassment.cfm

If you need immediate action take some vacation time and follow him for a week. Since he is a district manager he should be on the road a few days a week. I'm sure a dbag like him stops at strip joints for lunch every day.