Where can I find a list of the ward bosses (or, to use the euphism, district committeemen) of Chicago online?
Actually, didn’t see it there. (Probably because it’s a party (not a city) post.
Try http://www.cookcountydems.com/ward.htm
(And Chicago has wards, not districts, which may be the reason your search didn’t find a list.)
I found the relevent lists for both parties on party websites.