I mentioned this in my response to your other thread. Contact somebody there and they should be able to help you. They might have some advocacy articles there and stuff. Some of it is particular to NYC but some of it could just be general statistics on the benefits of cycling.
Also, check out your town or county's Department of Transportation (DOT) as they may have actual resources on bike commuting. I know some counties here where I live in NJ publish bike maps and good bike routes and they may have an actual bike coordinator who is in charge of all the bike paths and bike lanes.