Michel's in southwestern Germany

Hi-
I have been researching my family history for about fifteen years, and information on my paternal grandfather has been a real stone wall. His name was Henry (Heinrich) Michel. I have some eveidence that he was born in Reichenau, Germany on August 11, 1855. But beyond that, I am stuck on what he did after migrating to the US. If anyone has any experience in doing research in that part of Germany which has gone back and forth between Germany and France several times, I would appreciate any tips you may have. I believe that the Reichenau I am looking for is on Lake Constance, just above the Swiss border into Germany. If you would prefer to contact me directly, my email is don1936@gmail.com. Thanks for any help you can give me.
Don