Hey Travis!
They come in a little plastic bag, with just enough earth to cover the roots. Some folk wash this earth off by immersing the plant in a distilled water and Superthrive solution before repotting, but I just stuck the whole rootball in the new pot undisturbed. Additionally, this bit of earth is a good guide for getting the proper planting depth on the rhizome.
You will need a container (a 4" plastic pot is OK, though I have had 100% survival with a 12" pot with 4 plants in it) and a 50/50 peat/perlite or peat/sand mixture to plant them in. Canadian sphagnum peat moss is best. Put the pot in a saucer and keep the saucer filled with distilled water or rain water.
They will need sunlight, about 6 hours a day.
Most people lose about 20% of their rhizomes to shock, so get a few. At less than a buck apiece, you can't really go wrong.
The potted ones have a better survival rate--they may be bigger, too, though I don't know that for sure.
Steve