I've been typesetting books and journals with TeX since 1983, but almost exclusively in the humanities, not math/sciences. I have no training in this field -- I just try to copy and modify stuff I see.
Book design is my biggest worry -- I want to do something a little bit different but haven't always the time to explore or the skills to achieve what I find. Fonts are my biggest bug-a-boo -- can't identify a face to save my life. So I collect books on both instead!
Specialties in TeX: linguistics, critical editions.
Carleton Production Centre cthiele(at)ccs.carleton.ca