In all of my travels I have had this same question. My best results have invariably come from buying local handcrafts and especially for the children, the local instruments are hugely popular. Berimabau from Brazil, Maracas from Mexico, Flutes from Uruguay, etc. Maybe a veil or Abaya for a sister/lady friend. Something traditional yet beautiful.

I agree with the dried Dates mentioned above. Also the flavored tobacco from the Shishas. Some of the incense for teenagers is popular but strong for adults.

I also have brought home coffee table books of the places I lived to put on display for all to flip through. Hugely popular.

Remember, cheap will make them just as happy as expensive! The thought (and seeing you again, FINALLY) is truly what counts.