dried apples are like any other dried fruit.  They can be purchased at most grocery stores and certainly at places like Whole Foods or Trader Joe's.  We get ours at the local health food store, as they usually contain fewer additives.  They are often in fruit mixtures, but they can be bought by themselves.  They aren't crisp like a fresh apple, but then I can't imagine that an apple that had been frozen would be crisp either.