Yesterday on the Channel 4 segment about groundcover alternatives, I mentioned you can find good moss sources online. Here are the links I recommend:
~ Moss Acres
~ Spring Hill Nurseries
Pictured here is my shady front path that I'm cultivated moss in and around. There was a wonderful lawn of moss I saw on the Brookland Garden Tour a couple years ago, but I cannot find an image of it in my photo records. It was a backyard near the Franciscan Monastery and was impressive for its size, uniformity, and grooming. As anyone has tried to cultivate a nice patch of moss from scratch knows, it takes a lot of painstaking weeding if you want it to be perfect. I'm not personally into the tweezers and magnifying lens level of maintenance, but if you have the time and inclination, who am I to judge? I'm sure it is very Zen-like. For my lazy gardener maintenance regime, I just weed-whack the area every month or so down to below one inch. That usually takes care of any errant turfgrass and other weeds that are trying to start up in the moss.