I just started watching the show a few weeks ago (caught up on the first few episodes through www.cbs.com/innertube which rocks!) but i absolutely love the show, is there a good place to get the previous seasons other than buying a DVD?
I want to second what allmaple said up there, but I thought I'd unlock the thread to say this as well.
You can buy the current season's episodes for all three shows on iTunes, as well as the episodes from last season. That's not all of the older episodes, but it's at least a way to get the previous season for each show.