My DS isnt a fan of being changed either....its not fun huh!
I got a mobile type thing for his change table and that seemed to help him a fair bit, generally as soon as he hears the music he is totally captivated.
He would also scream the house down having a bath too....so I have just been slowly letting him have more time with less clothes on and he seems to be slowly calming down and getting used to being nakey lol
good luck, I hope you can find soemthing to calm your little one too...its hard hearing them scream like that!!