Sea salt is readily available at most grocery stores; for example, Walmart carries Morton Sea Salt at many of its locations. Grocers that specialize in organic foods are most likely to carry sea salt. For example, many Whole Foods locations stock Celtic Sea Salt.
If sea salt is not available at local grocery stores, it is easy to obtain online. Amazon.com, for example, lists a variety of sea salt brands for sale. As of 2014, a pound of Celtic Sea Salt costs about $10 from the online retailer. Sea salt is made from the evaporation of sea water, and it typically has a coarser texture than standard table salt.