I've got a tape that was part of a 'Pokémon: The First movie' promotion back in the day. It details a couple of changes between the japanese and american versions of the film, as told by some company big-wigs who nobody knows/cares about, who go into long winded speeches about how they went about dumbing it down for the audience.
But the most interesting thing about the video, is the section which shows a few snippets of the animé before it went onto air. It has different voice actors, original music and everything. Though the only characters you see iirc are Ash and Oak (Oak having a REALLY gruff sounding voice, while Ash sounds like a girl), whilst the likes of Spearow and Pidgey and Pikachu are featured. For the record, all of those pokémon keep their japanese voices.
