> I have been unable to find his name on a ships passenger list for 1885-1887.
It would have been EXTREMELY helpful, if you had mentioned WHERE you had looked for him as a passenger. If you checked the "Germans to America" series, then you probably should not be surprised that you did not find him. For the why, see http://www.uni-oldenburg.de/nausa/pitfal.htm
> It is possible that his name was mis-spelled enroute to America as 'Stillmaker'?
It is a possibility, but why should he be misspelled?
For some vague idea about the area of where your ancestor probably could have been from, check http://db.genealogy.net/cgi-bin/neumark.pl?name=Stellmacher&...