I saw there was an old post about this, but I'll start a fresh one. Just because.
I have used Motorblade before and Fritz is doing a great job. But in case you want to save money or just want to hang posters yourself I started a list of places that I have found. If you know of places, please add them to the list.
https://docs.google.com/spreadsheet/ccc?key=0ApUNi2j1xl_vdEdNTDBjdklkU01GU09MZ2xfaFAwS2c&usp=sharing
Wheeee,
Andreas