I also found some Fissidens growing in a local pond. Make sure you disinfect it well; I found two leeches in my bucket last time. You have to be careful, though, because if you're too harsh with the disinfecting, it will kill the moss.
the creek is in south side, in one of the parks. it can also be found in most of the spring fed creeks in any of the state parks. if you are able to find some, dont be greedy. not everything exists to be reaped and sold.