If I'm not mistaken, the order is:
Season 1, released by Animeigo (4 boxes, 13 DVDs as singles, plus 3 bonus disks only available in the boxes) [51 episodes]
Season 2, released by Sentai Filmworks (2 collections, sometimes marketed as "Fast and Furious") [26 episodes]
Full Throttle, upcoming from Sentai Filmworks (probably 2 collections) [23 episodes]
I'm not sure where the specials and movie fall into that order or their licensing/release status, though.
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Honou Productions.
Season 1, released by Animeigo (4 boxes, 13 DVDs as singles, plus 3 bonus disks only available in the boxes) [51 episodes]
Season 2, released by Sentai Filmworks (2 collections, sometimes marketed as "Fast and Furious") [26 episodes]
Full Throttle, upcoming from Sentai Filmworks (probably 2 collections) [23 episodes]
I'm not sure where the specials and movie fall into that order or their licensing/release status, though.
------------
Honou Productions.