Dear Dwight,
A sewing machine for shoes is completely different than a garment sewing machine. My students used to go to Cordwainer's College, part of the London School of Design, to learn shoemaking. Cordwainer means shoemaker, and the school has been there since the twelfth century. If you like London, have the time, and want to learn about shoes, the school has a summer program. The people who ran the program used to come to my school in Missouri to recruit, but they were older than I am, so are probably long retired. I don't know who's in charge now, but it's on the web.
As for other types of leather garments, your best bet is to go around to different shops and test drive to see what the different brands can do. One of my students designed a fabulous leather jacket with lots of topstitching, and the school machines wouldn't touch it. She went around town (St. Louis) and found a machine that made perfect topstitching, and she won best of show for the jacket. Sorry, I don't think she ever told us what machine she finally used to do it.
Teri