CD Japan has the entire 1963 and 1982 series on DVD. I've bought through CD Japan before and found them excellent to deal with. No English subtitles on these versions, and make sure your player matches the region encoding.
Places to get the first half of the 1982 Japanese dub with English subtitles on DVD:
Anime Toys OnlineAnime DVD MoviesABCToy4MeI haven't shopped from any of these places, I got mine through E-Bay. Note that this English subtitled release is probably a bootleg and has no region encoding, but the quality is excellent. Haven't seen the second half of this series anywhere.
Places to get the 2003 Japanese dub with English subtitles on DVD:
CrosstoyDon't know much about this one, but I think Jeffbert has it.
I'm not sure where you can get the original Japanese on VHS, but just do a search on Google and you'll come up with heaps. That's where I got the links above.