Prisonbreak season four just ended like two weeks ago or so, and I was just wondering if anyone knew either the release date that it is supposed to be on DVD, or a site that I could go to in the future to check.

I usually cheat. I just pull up amazon.com or a similar site and see what they have listed for the release date. They do have season 4 listed but no date yet. You can get them to email you when they get a release date.