New Bark Town

Prof. Elm, 9 tiles straight north of the lab entrance, gives you an Everstone when you show him the Togepi or Togetic from his aide's Egg.

Prof. Elm gives you a Master Ball once you hold the Rising Badge; he stands in his lab, 9 tiles straight north of the entrance.

Elm's Aide hands over 5 Poké Balls as you head out after giving Prof. Elm the Mystery Egg, 3 tiles straight north of the lab entrance.

Elm's Aide hands over a Potion as you head out after choosing your starter, 3 tiles straight north of the lab entrance.

Prof. Elm gives you the S.S. Ticket after you beat the Elite Four; he stands in his lab, 9 tiles straight north of the entrance.