If you have arrived early for departure at the airport in St. John's, check your luggage, and then head towards the Stanford Bank, which is opposite the airport. It has wonderful gardens around it.  It is a short walk to the Stanford Tower, and climbing it will give good views of the area, including the "Sticky Wicket" cricket ground.  Security guards are friendly, and will tell you the way.  It is free, and worth while.  The gardens are superb, and you could even see a wedding party there for photos.  It makes a great finish to your holiday.  If you're short of time do the gardens alone, but you can do it all in about 50 minutes.  And it's much better than waiting around at the airport!

Sticky Wicket - directly opposite the airport has a good clean modern restaurent and bar area.  If you've checked in at the airport and have time, this is recommended over the rather dated, basic and (after passport control) crowded airport facilities.

Although the departures waiting area is small and crowded it does have a reasonable range of souvenir and duty free shops.