Smalltalks usually come with some sort of graphical environment that facilitates the building of GUIs. Those environments usually also provide simpler graphical primitives you can draw with. In fact, if all you want is LOGO, you can use the Pen class (a standard ST-80 class) in Squeak or Pharo as a LOGO turtle:
p := Pen new.
360 timesRepeat: [p go: 1; turn: 1].
that will draw a circle.
4 timesRepeat: [p go: 100; turn: 90].
and that, a square.
More complicated stuff can be done with Morphic and eToys.