An Amazon listing has gone up for 'Season 1' of JoJo's Bizarre Adventure, listing it for a July 28th release, from Warner Home Video. ANN has confirmed through Viz Media – who are the master merchandise license-holder for the franchise – that they are not involved in this release, though they are releasing the original manga.
Not much else is known about this release as of now. 'Season 1' might not even mean the original anime series adapting Parts 1 and 2 of the manga, as a 'test dub' of a few 'Season 2' episodes which adapts Part 3 of the manga was released online last year. Hopefully this is a release of the first anime however, before they can move on to the later material at a later date.