Seeing as Heroes Season 3 hasn't finished in America as yet, it won't be released too soon. However if it follows the trend of seasons 1 and 2, it should have an American release date in August/September about a month before season 4 airs.
Season 2 will be released mid August of 2008 as for season 3 - best guess, sometime in September of 2008
Season 3 of Glee is coming out August 14, 2012 on DVD.
Complete 1st Season will be coming to DVD on September 16th, 2008
The second season is coming out on DVD August 30th, 2011.
October 12th
Hi When Will Merlin Season 5 Come To DVD?
Yes, it has been released.
It's already out on DVD.
Ghost Adventures Season 5 will currently be coming out on DVD on February 25, 2014 however no announcements have been made for the DVD release of Seasons 6 and 7.
eventually
There are now H2O: Just Add Water DVDs for the United States. There is one set for each season and a $48 one for all three seasons combined. Season 1 DVD about $20 Season 2 DVD about $20 Season 3 DVD about $20
Yes, it is coming up.