Whether you are an Union officer, a steward, a business agent or more importantly a rank and file member, these sites provide a wealth of information.
NABTU: North American Building Trades Unions
Change To Win: Strategic Organizing Center
Unions For All: Fight For Our Right To Unionize
UnionBase: Home of the Virtual Labor Movement
UnionCoded: Labor Union Website Platform
Labor Notes: Network for rank-and-file union members and grassroots labor activists.