Have you ever tried to figure out which team was where? What "type" a league is? It can get confusing, especially when a group of "leagues" is a league itself. So, somewhat hierarchically, followed by breakdowns of each league ....
American Collegiate Hockey Association (ACHA); web page currently non-operational; appears to be "super-league" of college leagues.
NCAA also has a men's hockey sub-arm.
Atlantic Hockey (new grouping; last season these schools were MAAC)
Central Collegiate Hockey Association (CCHA)
College Hockey America (CHA)
Eastern Collegiate Athletic Conference (ECAC)
Hockey East (HE)
Western Collegiate Hockey Association (WCHA)
ECAC East, 9 teams
ECAC Northeast, 17 teams
ECAC West, 6 teams
MCHA, 5 teams
MIAC, 9 teams
NCHA, 8 teams
NESCAC, 10 teams
SUNYAC, 8 teams
D-III Independent, 1 team