Season 1
by Galvatron and Ragey
Oh God.
Rhino released the season in the US as both individual volumes and a full box
set with bonus feature disc. There's some extras on the remastering process,
pointing out of animation errors (ANIMATOR'S HAIR), some dubbed clips from
Masterforce and Victory, bumpers, the script to Transport to Oblivion
and footage of BotCon 2001. It's pretty expensive.
Madman Entertainment released their own version of the season in Australia, and it is downright impossible to actually find out if it contains anything more than that.
Metrodome's UK release has different extras, such as a quiz, footage from BotCon 2004, character profiles, episode scripts and a "hidden Easter egg" that the site's description promises. What a mystery! Though it bugs me how the term "hidden" Easter egg is used. An Easter egg is meant to be hidden. At least, they are in the States. Over here you walk into a store and there they are!
There's also a ton of VHS tapes which are a lot cheaper than the American box sets, but they only contain like one or two episodes, so why bother?
Amazon US: Rhino DVD
Amazon UK: Metrodome DVD