Mosses are brypohytes (br-eye-yo-fights). They are plants. So the taxonomy (which is what you are asking about ) would be: Kingdom: plants, division: bryophytes, classes: takakiopsida, sphagnopsid, andreaeopsida, andreaeobryopsida, polytrichopsida, bryopsida, family: a subset of the above, genus: you can look it up, species - that is very "specific" (get it?)... You can buy sphagnum moss at most nurseries...