Banned In Australia: The episode "Amazon Kevin", which features a Crocodile Hunter Captain Ersatz, was never aired in the country again in the wake of Steve Irwin's unfortunate demise. Watch the episode for yourself, and you'll know why.
In-episode example: When everyone at CDMS are forced to wear school uniforms, everyone, except Dickie (who is British of course), Adam and Principal Pixiefrog, started speaking in obviously fake British accents.
Speaking of Tom Kenny, David Coppertrout also qualifies.
Keep Circulating the Tapes: Two DVD volumes of the show do exist but they're Region 4 and region locked. The entire series IS available on iTunes however, and the first season is available on Netflix.