the first series of World of Springfield figures was released
in the USA and Canada. Approximately every six months,
a new series of figures as released with different characters.
Also released were World of Springfield "Environments"
which were like replicas of different scenes from the
show and you could 'plug' in the figures to the environments.
Each character would say a couple of catchphrases depending
on the environment it was plugged into. By far, the WOS
figures and environments have been my favourite Simpsons
collectible/toy. I've pretty much collected everything
and if you're still looking for that hard to find character,
follow the "Buy it" link beside the figure/environment.